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COVID-19 Vaccination and Intent for Vaccination of Adults With Reported Medical Conditions

  • Peng-jun Lu
    Correspondence
    Address correspondence to: Peng-jun Lu, MD, PhD, Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, 1600 Clifton Road Northeast, Mail Stop H24-4, Atlanta GA 30329.
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Mei-Chuan Hung
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia

    Leidos Inc., Atlanta, Georgia
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  • Hannah L. Jackson
    Affiliations
    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Jennifer L. Kriss
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Anup Srivastav
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia

    Leidos Inc., Atlanta, Georgia
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  • David Yankey
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Tammy A. Santibanez
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • James Tseryuan Lee
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Lu Meng
    Affiliations
    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Hilda Razzaghi
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Carla L. Black
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Laurie D. Elam-Evans
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia
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  • James A. Singleton
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, Georgia

    CDC COVID-19 Response Team, Global Health Protection and Security, Centers for Disease Control and Prevention, Atlanta, Georgia
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      Introduction

      Individuals with certain medical conditions are at substantially increased risk for severe illness from COVID-19. The purpose of this study is to assess COVID-19 vaccination among U.S. adults with reported medical conditions.

      Methods

      Data from the National Immunization Survey-Adult COVID Module collected during August 1–September 25, 2021 were analyzed in 2022 to assess COVID-19 vaccination status, intent, vaccine confidence, behavior, and experience among adults with reported medical conditions. Unadjusted and age-adjusted prevalence ratios (PRs and APRs) were generated using logistic regression and predictive marginals.

      Results

      Overall, COVID-19 vaccination coverage with ≥1 dose was 81.8% among adults with reported medical conditions, and coverage was significantly higher compared with those without such conditions (70.3%) Among adults aged ≥18 years with medical conditions, COVID-19 vaccination coverage was significantly higher among those with a provider recommendation (86.5%) than those without (76.5%). Among all respondents, 9.2% of unvaccinated adults with medical conditions reported they were willing or open to vaccination. Adults who reported high risk medical conditions were more likely to report receiving a provider recommendation, often or always wearing masks during the last 7 days, concerning about getting COVID-19, thinking the vaccine is safe, and believing a COVID-19 vaccine is important for protection from COVID-19 infection than those without such conditions.

      Conclusions

      Approximately 18.0% of those with reported medical conditions were unvaccinated. Receiving a provider recommendation was significantly associated with vaccination, reinforcing that provider recommendation is an important approach to increase vaccination coverage. Ensuring access to vaccine, addressing vaccination barriers, and increasing vaccine confidence can improve vaccination coverage among unvaccinated adults.

      INTRODUCTION

      Persons with certain medical conditions such as lung disease, heart disease, diabetes, renal disease, liver disease, and cancer are at substantially increased risk for severe illness from coronavirus disease 2019 (COVID-19), including hospitalization, admission to the intensive care unit, intubation or mechanical ventilation, and death.
      • Kim L
      • Garg S
      • O'Halloran A
      • et al.
      Risk factors for intensive care unit admission and in-hospital mortality among hospitalized adults identified through the US coronavirus disease 2019 (COVID-19)-Associated Hospitalization Surveillance Network (COVID-NET).
      ,
      • Dooling K
      • Marin M
      • Wallace M
      • et al.
      The Advisory Committee on Immunization Practices’ updated interim recommendation for allocation of COVID-19 vaccine - United States, December 2020.
      Studies showed that nearly 90% of persons hospitalized for COVID-19 have an underlying medical condition.
      • Dooling K
      • Marin M
      • Wallace M
      • et al.
      The Advisory Committee on Immunization Practices’ updated interim recommendation for allocation of COVID-19 vaccine - United States, December 2020.
      The risk for COVID-19–associated hospitalization increases with an increasing number of medical conditions.
      • Dooling K
      • Marin M
      • Wallace M
      • et al.
      The Advisory Committee on Immunization Practices’ updated interim recommendation for allocation of COVID-19 vaccine - United States, December 2020.
      Vaccination of persons with these conditions is a key public health strategy in preventing COVID-19–related morbidity and mortality. Although the Advisory Committee on Immunization Practices (ACIP) initially prioritized persons with certain medical conditions for receiving COVID-19 vaccination when vaccine supplies were limited, monitoring COVID-19 vaccination coverage among adults with these conditions at a population level has been challenging. The objective of this study was to assess COVID-19 vaccination status, intent, vaccine confidence, behavior, and experience among U.S. adults with reported medical conditions that increased their risk of COVID-19 using data from the National Immunization Survey-Adult COVID Module (NIS-ACM).
      About the National immunization surveys (NIS).

      METHODS

      Study Sample

      The NIS-ACM is a national telephone survey conducted by the Centers for Disease Control and Prevention (CDC). Interviews were conducted in English, Spanish, and other languages among U.S. adults aged ≥18 years using a random-digit-dialed sample of cellular telephone numbers. The data in this study were collected during August 1, 2021–September 25, 2021, and data were analyzed in 2022. Receipt of ≥1 dose of COVID-19 vaccine was based on response to the question Have you received at least one dose of a COVID-19 vaccine? Adults reporting not receiving a vaccine were asked How likely are you to get a COVID-19 vaccine? Would you say you would definitely get a vaccine, probably get a vaccine, probably not get a vaccine, definitely not get a vaccine, or are not sure? Survey questions also collected information on vaccine confidence, behaviors, and experiences such as concern about getting COVID-19, thinking that COVID-19 vaccines are safe, believing that COVID-19 vaccines are important for protection from COVID-19, whether the respondent often or always wore a mask, and whether the respondent had difficulty in getting a COVID-19 vaccine (e.g., difficulty in getting an appointment online, difficulty in knowing where to get vaccinated, difficulty in getting to vaccination sites). Respondents were asked Do you have a health condition that may put you at higher risk for COVID-19? Those answering yes were considered high-risk medical conditions (referred to as high-risk medical conditions in the remaining part of this paper). To further identify what type of conditions people have, those answering yes to the question mentioned earlier were further asked Can you tell me what that is? Adults aged ≥65 years who only reported older age as a health condition were not considered to have a high-risk medical condition. Information on demographic and access-to-care characteristics and whether the respondent ever had COVID-19 were also collected.
      About the National immunization surveys (NIS).

      Measures

      COVID-19 vaccination coverage was stratified by demographic and access-to-care characteristics. Race/ethnicity was classified as non-Hispanic White, non-Hispanic Black, Hispanic, and non-Hispanic Others (including non-Hispanic Asians, non-Hispanic American Indian/Alaska Native, non-Hispanic Pacific Islander/Native Hawaiian, and other or multiple race). Urbanicity status was derived on the basis of the centroid of the ZIP code of residence, categorized as metropolitan statistical area (MSA) principal city, MSA nonprincipal city, and non-MSA.
      • Williams CL
      • Walker TY
      • Elam-Evans LD
      • et al.
      Factors associated with not receiving HPV vaccine among adolescents by metropolitan statistical area status, United States, National Immunization Survey-Teen, 2016–2017.
      Social vulnerability index (SVI) was categorized as low, moderate, or high on the basis of the county of residence (CDC/Agency for Toxic Substances and Disease Registry) using tertiles of SVI score.

      CDC/ATSDR social vulnerability index. Centers for Disease Control and Prevention, Agency for Toxic Substances and Disease Registry. https://www.atsdr.cdc.gov/placeandhealth/svi/index.html. Updated March 15, 2022. Accessed September 30, 2021.

      Statistical Analysis

      Data were analyzed using SAS (version 9.4) and SUDAAN (version 11.0.1) (Research Triangle Institute). All percentages were weighted to represent the non-institutionalized U.S. adult population. Survey weights were also calibrated to state-level vaccine administration data reported to CDC.

      COVID-19 Vaccination trends in the United States. Centers for Disease Control and Prevention. https://data.cdc.gov/Vaccinations/COVID-19-Vaccinations-in-the-United-States-Jurisdi/unsk-b7fc. Updated July 7, 2022. Accessed March 8, 2022.

      Unadjusted prevalence ratios (PRs) and age-adjusted prevalence ratios were generated using logistic regression and predictive marginals.
      • Witt MB
      • Spagnola KE.
      Using predictive marginals to produce standardized estimates.
      T-tests were used to determine the differences between groups with statistical significance at p<0.05. This activity was reviewed by CDC and was conducted in consistence with applicable federal law and CDC policy.

      RESULTS

      The response rate was 20.5% in August and 20.9% in September. Of the 136,619 adults who completed an interview, 39,365 (28.3%) reported that they had high-risk medical conditions. Coverage with ≥1 dose of COVID-19 vaccine was 81.8% among adults with reported high-risk medical conditions, and coverage was significantly higher than among those who did not report such conditions (70.3%) (Table 1). Overall, 9.2% of adults with reported high-risk medical conditions still planned to get vaccinated or were unsure, whereas 9.0% probably will not or definitely will not get vaccinated. Adults with reported high-risk medical conditions were half as likely to report that they were unvaccinated and would probably or definitely not get vaccinated than those who did not report such conditions (9.0% vs 16.6%). Percentage estimates of reporting “probably will not or definitely will not get vaccinated” were significantly lower among those with reported high-risk medical conditions than among those without such conditions within each age group (18–49, 50–64, and ≥65 years), with estimate highest in the youngest age group. Among adults with reported high-risk medical conditions, the prevalence of provider recommendation for COVID-19 vaccine was 50.2% among those aged 18–49 years, 54.5% among those aged 50–64 years, and 53.3% among those aged ≥65 years. Among adults not reporting such conditions, the prevalence of provider recommendation for COVID-19 vaccine was 33.0% among those aged 18–49 years, 36.3% among those aged 50–64 years, and 38.2% among those aged ≥65 years.
      Table 1COVID-19 Vaccination, Intent, and Vaccine Confidence/Behavior by Status of Reported Medical Conditions That Increased Their Risk of COVID-19 Among Adults Aged ≥18 Years, NIS-ACM, August 1–September 25, 2021
      Persons aged ≥18 yearsPersons aged 18–49 yearsPersons aged 50–64 yearsPersons aged ≥65 years
      COVID-19 vaccine and vaccination related characteristicsTotal (N=136,619)Persons who reported that they had medical conditions that increased their risk of COVID-19 (n=39,365)Persons who did not report that they had medical conditions that increased their risk of COVID-19 (n=95,520)Persons who reported that they had medical conditions that increased their risk of COVID-19 (n=13,161)Persons who did not report that they had medical conditions that increased their risk of COVID-19 (n=53,227)Persons who reported that they had medical conditions that increased their risk of COVID-19 (n=13,523)Persons who did not report that they had medical conditions that increased their risk of COVID-19 (n=23,411)Persons who reported that they had medical conditions that increased their risk of COVID-19 (n=12,134)Persons who did not report that they had medical conditions that increased their risk of COVID-19 (n=17,240)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      Vaccination coverage (≥1 dose)73.3 (72.9, 73.8)81.8 (80.9, 82.6)70.3 (69.7, 70.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      70.9 (69.2, 72.4)62.1 (61.3, 62.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      83.8 (82.4, 85.1)78.3 (77.1, 79.4)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      92.8 (91.8, 93.7)90.4 (89.4, 91.3)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      Vaccination intent among unvaccinated adults
       Definitely plan to get vaccinated2.9 (2.7, 3.1)2.6 (2.3, 3.0)3.0 (2.7, 3.2)4.0 (3.3, 4.8)4.0 (3.6, 4.4)2.5 (2.0, 3.1)1.8 (1.5, 2.2)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      1.1 (0.7, 1.5)0.7 (0.5, 1.0)
       Probably will get vaccinated or unsure9.3 (8.9, 9.6)6.6 (6.1, 7.2)10.2 (9.8, 10.6)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      11.1 (10.0, 12.4)13.4 (12.8, 14.0)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      5.1 (4.4, 6.0)7.2 (6.5, 8.0)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      2.9 (2.4, 3.6)2.7 (2.3, 3.3)
       Probably or definitely will not get vaccinated14.5 (14.1, 14.9)9.0 (8.4, 9.6)16.6 (16.1, 17.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      14.0 (12.8, 15.3)20.6 (19.9, 21.3)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      8.6 (7.6, 9.7)12.8 (11.9, 13.7)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      3.2 (2.7, 3.9)6.1 (5.4, 6.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      Vaccine confidence, behavior, experience, and other characteristics
       Concerned about getting COVID-19 (very or moderately)49.1 (48.6, 49.6)62.8 (61.9, 63.7)43.7 (43.1, 44.3)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      59.2 (57.6, 60.7)40.1 (39.3, 40.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      64.7 (63.1, 66.3)47.9 (46.7, 49.2)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      65.4 (63.7, 67.0)51.5 (50.0, 53.0)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Thinks a COVID-19 vaccine is safe (completely or very)62.2 (61.7, 62.7)67.5 (66.5, 68.4)60.3 (59.7, 61.0)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      59.2 (57.6, 60.9)54.3 (53.5, 55.2)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      67.4 (65.8, 69.0)64.6 (63.3, 65.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      77.5 (76.0, 79.0)77.3 (75.9, 78.6)
       Thinks a COVID-19 vaccine is important protection (very or somewhat)80.4 (80.0, 80.9)88.5 (87.8, 89.1)77.4 (76.9, 78.0)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      82.7 (81.3, 84.0)72.7 (71.9, 73.5)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      89.4 (88.2, 90.4)80.8 (79.7, 81.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      94.6 (93.8, 95.3)91.0 (90.0, 91.8)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Had friends/family that were vaccinated (almost all or many)67.9 (67.4, 68.3)72.3 (71.4, 73.2)66.3 (65.7, 66.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      66.9 (65.3, 68.4)61.3 (60.5, 62.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      71.4 (69.8, 72.9)70.1 (68.9, 71.3)79.8 (78.3, 81.2)80.2 (78.9, 81.3)
       Provider recommendation of the COVID-19 vaccine39.6 (39.1, 40.1)52.5 (51.6, 53.5)34.5 (34.0, 35.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      50.2 (48.6, 51.8)33.0 (32.3, 33.7)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      54.5 (52.8, 56.1)36.3 (35.1, 37.5)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      53.3 (51.6, 55.1)38.2 (36.8, 39.7)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Often or always wore masks during last 7 days68.0 (67.5, 68.4)73.5 (72.6, 74.3)65.9 (65.3, 66.4)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      72.5 (71.1, 74.0)65.3 (64.6, 66.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      73.5 (72.1, 74.9)64.5 (63.3, 65.7)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      74.7 (73.1, 76.2)69.6 (68.2, 70.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      Vaccination difficulty among unvaccinated adults
       Difficulty getting vaccinated (very or somewhat)13.6 (12.9, 14.5)17.9 (15.9, 20.0)12.5 (11.6, 13.4)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      17.7 (15.1, 20.6)12.8 (11.8, 13.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      16.3 (13.1, 20.2)10.6 (8.9, 12.6)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      24.3 (18.8, 30.8)12.9 (9.7, 17.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Difficulty getting an appointment online4.1 (3.6, 4.6)6.4 (5.2, 7.8)3.5 (3.1, 4.0)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      5.7 (4.2, 7.7)3.5 (3.0, 4.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      5.8 (4.0, 8.4)3.9 (2.9, 5.1)11.3 (7.6, 16.4)3.9 (2.6, 5.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Difficulty with not knowing where to get vaccinated5.1 (4.6, 5.7)7.2 (5.9, 8.8)4.6 (4.1, 5.2)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      7.4 (5.7, 9.7)4.9 (4.3, 5.6)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      6.2 (4.2, 9.1)3.7 (2.7, 5.0)9.3 (6.2, 13.7)4.5 (2.8, 7.2)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Hard to get to vaccination sites5.2 (4.7, 5.8)8.3 (7.0, 9.8)4.3 (3.8, 4.9)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      8.0 (6.3, 10.2)4.6 (4.0, 5.3)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      5.7 (3.9, 8.4)3.3 (2.5, 4.4)16.0 (11.6, 21.6)3.7 (2.2, 6.2)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
       Vaccination sites are not open at convenient times6.7 (6.2, 7.3)9.4 (8.0, 11.1)6.0 (5.4, 6.7)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      10.4 (8.3, 12.8)6.7 (5.9, 7.5)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      7.7 (5.6, 10.5)3.8 (2.9, 5.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      9.7 (6.4, 14.5)3.6 (2.1, 6.1)
      p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions. NIS-ACM, National Immunization Survey-Adult COVID Module.
      Note: Boldface indicates statistical significance (p<0.05).
      a Weighted percentages.
      b p<0.05 by t test for comparisons between persons who reported medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions.NIS-ACM, National Immunization Survey-Adult COVID Module.
      Adults who reported high-risk medical conditions were more likely to report receiving a provider recommendation for a COVID-19 vaccine (52.5% vs 34.5%), often or always wearing masks during the last 7 days (73.5% vs 65.9%), being concerned about getting COVID-19 (62.8% vs 43.7%), thinking that the vaccine is safe (67.5% vs 60.3%), and believing that a COVID-19 vaccine is important for protection from COVID-19 infection than those who did not report high-risk medical conditions (88.5% vs 77.4%) (Table 1). Larger percentages of unvaccinated adults who reported high-risk medical conditions reported difficulties in getting a COVID-19 vaccine (e.g., difficulty in getting an appointment online, difficulty in knowing where to get vaccinated, and difficulty in getting to vaccination sites) than those who did not report medical conditions (Table 1).
      Among adults who reported high-risk medical conditions, COVID-19 vaccination coverage among those aged 50–64 years (83.8%) and ≥65 years (92.8%) was significantly higher than that among those aged 18–49 years (70.9%) (Table 2). Vaccination coverage among adults reporting high-risk medical conditions was significantly lower among non-Hispanic Blacks (80.3%) and individuals of non-Hispanic other race/ethnicity (76.6%) than among non-Hispanic Whites (82.8%) (p<0.05). In addition, among adults who reported high-risk medical conditions, those who lived at or above the poverty level; had some college or higher education; had health insurance; had perceived mental health status classified as excellent, very good, or good; had received a vaccine other than COVID-19 in the past 2 years; and had received a provider recommendation for a COVID-19 vaccine had higher vaccination coverage than the respective reference groups indicated in Table 2. Women, those living in a non-MSA, those living in a moderate or high SVI county, those who were frontline or essential workers, those with a disability, and those with a previous COVID-19 infection had lower vaccination coverage than the respective reference groups (Table 2). Factors associated with COVID-19 vaccination among adults who did not report high-risk medical conditions were generally similar to factors among those who reported such conditions (Table 2).
      Table 2COVID-19 Vaccination Coverage of Adults Aged ≥18 Years by Status of Reported Medical Conditions That Increased Their Risk of COVID-19 and Sociodemographic and Access-to-Care Characteristics, NIS-ACM, August 1–September 25, 2021
      Persons who reported that they had medical conditions that increased their risk of COVID-19Persons who did not report that they had medical conditions that increased their risk of COVID-19Unadjusted PR comparing vaccination coverage for persons who reported that medical conditions increased their risk of COVID-19 with that for those who did not report those medical conditionsAge adjusted PR (APR) comparing vaccination coverage for persons who reported that medical conditions increased their risk of COVID-19 with that for persons who did not report those medical conditions
      Vaccinated (at least 1 dose)Vaccinated (at least 1 dose)
      Characteristicsn%
      Weighted percentages.
      (95% CI)
      n%
      Weighted percentages.
      (95% CI)
      PR (95% CI)APR (95% CI)
      Total39,30281.8

      (80.9, 82.6)
      95,14070.3

      (69.7, 70.9)
      1.16

      (1.15, 1.18)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.09

      (1.08, 1.11)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Age group, years
       18–49
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      13,13670.9

      (69.2, 72.4)
      53,05862.1

      (61.3, 62.9)
      1.14

      (1.11, 1.17)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      NA
       50–6413,50483.8

      (82.4, 85.1)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      23,31678.3

      (77.1, 79.4)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.07

      (1.05, 1.09)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      NA
       ≥6512,12092.8

      (91.8, 93.7)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      17,17990.4

      (89.4, 91.3)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.03

      (1.01, 1.04)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      NA
      Sex
       Male
      Reference level.
      16,77983.3

      (82.0, 84.5)
      48,26967.7

      (66.9, 68.6)
      1.23

      (1.21, 1.25)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.14

      (1.11, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Female22,26180.8

      (79.7, 81.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      46,08673.4

      (72.5, 74.2)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.10

      (1.08, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.05

      (1.03, 1.07)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Race/ethnicity
       White, non-Hispanic
      Reference level.
      25,03782.8

      (81.8, 83.7)
      59,71571.3

      (70.5, 72.0)
      1.16

      (1.14, 1.18)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.10

      (1.08, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Black, non-Hispanic5,35980.3

      (78.0, 82.4)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      10,54063.2

      (61.4, 65.0)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.27

      (1.22, 1.32)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.16

      (1.11, 1.21)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Hispanic4,52982.3

      (79.8, 84.5)
      11,74070.2

      (68.5, 71.8)
      1.17

      (1.13, 1.22)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.09

      (1.05, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Other, non-Hispanic3,36376.6

      (73.1, 79.7)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      10,29576.1

      (74.2, 77.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.01

      (0.96, 1.06)
      0.97

      (0.92, 1.02)
      Urbanicity
       MSA, principal city
      Reference level.
      13,43282.5

      (81.0, 83.9)
      34,08272.7

      (71.7, 73.7)
      1.13

      (1.11, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.07

      (1.04, 1.09)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       MSA, nonprincipal city18,63882.9

      (81.8, 84.0)
      44,21271.4

      (70.5, 72.2)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.16

      (1.14, 1.18)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.09

      (1.07, 1.11)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Non-MSA7,23275.9

      (73.7, 78.0)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      16,84659.8

      (58.2, 61.4)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.27

      (1.22, 1.32)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.17

      (1.12, 1.22)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      SVI of county of residence
      CDC/Agency for Toxic Substances and Disease Registry Social Vulnerability Index uses 15 U.S. Census variables to help officials identify communities that may need support before, during, or after disasters.
       Low
      Reference level.
      11,35784.3

      (82.7, 85.7)
      29,23774.8

      (73.7, 75.8)
      1.13

      (1.10, 1.15)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.07

      (1.05, 1.10)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Moderate13,20581.5

      (80.0, 82.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      31,61472.4

      (71.4, 73.4)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.13

      (1.10, 1.15)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.06

      (1.04, 1.09)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       High10,57381.6

      (80.0, 83.0)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      22,85267.1

      (65.9, 68.3)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.22

      (1.18, 1.25)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.13

      (1.10, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Household income
       Below poverty
      Reference level.
      4,43066.9

      (64.2, 69.5)
      7,62958.6

      (56.6, 60.7)
      1.14

      (1.08, 1.20)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.04

      (0.99, 1.10)
       Above poverty, <$75,00013,40482.0

      (80.6, 83.3)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      28,59967.7

      (66.6, 68.8)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.21

      (1.18, 1.24)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.12

      (1.09, 1.15)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Above poverty, ≥$75,00013,40489.2

      (87.9, 90.3)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      38,82578.1

      (77.1, 79.0)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.14

      (1.12, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.10

      (1.08, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Unknown income8,06480.4

      (78.5, 82.1)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      20,08767.2

      (65.9, 68.5)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.20

      (1.16, 1.23)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.11

      (1.07, 1.15)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Education level
       High school graduate or less
      Reference level.
      10,00376.5

      (75.0, 78.0)
      22,53661.4

      (60.2, 62.5)
      1.25

      (1.21, 1.28)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.12

      (1.09, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Some college12,08979.5

      (77.9, 80.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      24,89368.1

      (66.9, 69.2)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.17

      (1.14, 1.20)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.10

      (1.07, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       ≥College graduate16,12192.0

      (91.0, 92.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      44,78784.4

      (83.6, 85.2)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.09

      (1.08, 1.11)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.06

      (1.05, 1.08)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Health insurance
       Insured36,45482.9

      (82.1, 83.8)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      83,83273.2

      (72.5, 73.8)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.13

      (1.12, 1.15)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.08

      (1.06, 1.09)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Not insured
      Reference level.
      1,84164.2

      (60.0, 68.2)
      8,35652.1

      (50.2, 54.0)
      1.23

      (1.14, 1.33)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.13

      (1.05, 1.21)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Mental health
       Excellent, very good, or good33,44283.0

      (82.2, 83.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      85,74370.4

      (69.7, 71.0)
      1.18

      (1.16, 1.20)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.10

      (1.09, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       Fair or poor
      Reference level.
      5,59075.7

      (73.3, 77.9)
      8,80470.0

      (68.0, 71.9)
      1.08

      (1.04, 1.13)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.03

      (0.99, 1.07)
      Frontline and essential workers
      Essential workers included those in health care, social service, preschool or daycare, K-12 school, other schools and instructional settings, first response, death care, correctional facility, food and beverage store, agriculture, forestry, fishing, or hunting, food manufacturing facility, non-food manufacturing facility, public transit, and U. S. Postal Service and other essential workers.
       Yes10,37579.3

      (77.6, 80.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      31,86867.0

      (65.9, 68.1)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.18

      (1.15, 1.22)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.11

      (1.09, 1.14)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       No
      Reference level.
      28,45782.8

      (81.8, 83.7)
      61,63372.4

      (71.6, 73.1)
      1.14

      (1.13, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.08

      (1.06, 1.10)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Disability
      Disability was defined as an affirmative response to the following survey question: Do you have serious difficulty seeing, hearing, walking, remembering, making decisions, or communicating? APR, adjusted prevalence ratio; CDC, Centers for Disease Control and Prevention; K-12, kindergarten to 12th grade; MSA, metropolitan statistical area; NA, not applicable; NIS-ACM, National Immunization Survey-Adult COVID Module; PR, prevalence ratio; SVI, social vulnerability index.
       Yes (any)6,83178.2

      (76.3, 80.0)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      4,68170.8

      (68.1, 73.3)
      1.11

      (1.06, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.08

      (1.03, 1.14)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       No
      Reference level.
      32,38182.6

      (81.7, 83.5)
      90,34670.3

      (69.6, 70.9)
      1.18

      (1.16, 1.19)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.11

      (1.09, 1.12)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Ever had COVID-19
       Yes6,55467.6

      (65.4, 69.8)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      16,69955.8

      (54.3, 57.2)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.21

      (1.16, 1.26)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.11

      (1.07, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       No
      Reference level.
      32,26285.4

      (84.6, 86.3)
      77,36674.4

      (73.7, 75.0)
      1.15

      (1.13, 1.16)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.09

      (1.07, 1.10)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Received any vaccine that was not a COVID-19 vaccine in the past 2 years
       Yes26,45890.1

      (89.3, 90.9)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      51,30986.1

      (85.4, 86.8)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.05

      (1.03, 1.06)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.02

      (1.00, 1.03)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       No
      Reference level.
      12,64167.0

      (65.4, 68.7)
      43,22256.2

      (55.3, 57.1)
      1.19

      (1.16, 1.23)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.09

      (1.6, 1.13)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Provider recommendation of the COVID-19 vaccine
       Yes21,36786.5

      (85.5, 87.5)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      35,12277.6

      (76.6, 78.6)
      p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      1.11

      (1.10, 1.13)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.07

      (1.06, 1.09)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
       No
      Reference level.
      17,51576.5

      (75.2, 77.8)
      59,08566.3

      (65.5, 67.1)
      1.15

      (1.13, 1.18)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      1.06

      (1.04, 1.08)
      p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      Note: Boldface indicates statistical significance (p<0.05).
      a Weighted percentages.
      b p<0.05 by t test for comparisons of vaccination coverage between persons who reported that they had medical conditions that increased their risk of COVID-19 and persons who did not report those medical conditions within each level of each characteristic.
      c p<0.05 by t test for comparisons of vaccination coverage within each variable with that at the indicated reference level.
      d Reference level.
      e CDC/Agency for Toxic Substances and Disease Registry Social Vulnerability Index uses 15 U.S. Census variables to help officials identify communities that may need support before, during, or after disasters.
      f Essential workers included those in health care, social service, preschool or daycare, K-12 school, other schools and instructional settings, first response, death care, correctional facility, food and beverage store, agriculture, forestry, fishing, or hunting, food manufacturing facility, non-food manufacturing facility, public transit, and U. S. Postal Service and other essential workers.
      g Disability was defined as an affirmative response to the following survey question: Do you have serious difficulty seeing, hearing, walking, remembering, making decisions, or communicating?APR, adjusted prevalence ratio; CDC, Centers for Disease Control and Prevention; K-12, kindergarten to 12th grade; MSA, metropolitan statistical area; NA, not applicable; NIS-ACM, National Immunization Survey-Adult COVID Module; PR, prevalence ratio; SVI, social vulnerability index.
      The PRs comparing vaccination coverage among adults who reported high-risk medical conditions with that among those who did not report these conditions were significantly higher across each level of all sociodemographic and access-to-care characteristics except for non-Hispanic other race/ethnicity (Table 2). Age-adjusted PRs were also significantly higher across each level of all sociodemographic and access-to-care characteristics except for non-Hispanic other race/ethnicity, those with household income below poverty, and adults with perceived mental health status classified as fair or poor.
      The most prevalent medical conditions reported among adults aged ≥18 years with reported high-risk medical conditions were chronic lung diseases (7.4%) and diabetes (7.3%), followed by heart diseases (5.4%), overweight (2.1%), and immunocompromise (2.0%); the least prevalent conditions were sickle cell disease, having received an organ or blood transplant, dementia or other neurologic conditions, and HIV infection (0.1% for each of those 4 conditions) (Table 3). The prevalence of each medical condition among adults aged 50–64 years and ≥65 years was generally higher than among those aged 18–49 years.
      Table 3Vaccination Coverage (≥1 Dose) by Reported High-Risk Medical Conditions Among Adults Aged ≥18 Years, U.S. NIS-ACM, August 1–September 25, 2021
      Persons aged ≥18 yearsPersons aged 18–49 yearsPersons aged 50–64 yearsPersons aged ≥65 years
      High-risk medical conditionsPrevalence of conditionsCOVID-19 vaccination coverage (≥1 dose)Prevalence of conditionsCOVID-19 vaccination coverage (≥1 dose)Prevalence of conditionsCOVID-19 vaccination coverage (≥1 dose)Prevalence of conditionsCOVID-19 vaccination coverage (≥1 dose)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      %
      Weighted percentages.
      (95% CI)
      Chronic lung diseases
      Chronic lung disease includes COPD, asthma (moderate to severe), interstitial lung disease, cystic fibrosis, and pulmonary hypertension.
      7.4

      (7.1, 7.7)
      78.6

      (76.9, 80.3)
      6.2

      (5.8, 6.5)
      69.1

      (66.2, 71.8)
      8.6

      (8.0, 9.2)
      82.5

      (79.4, 85.3)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      9.4

      (8.8, 10.1)
      90.8

      (88.2, 92.8)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Heart diseases
      Heart disease includes heart failure, coronary artery disease, cardiomyopathies, or hypertension.
      5.4

      (5.2, 5.7)
      83.9

      (82.1, 85.6)
      2.2

      (2.0, 2.4)
      65.9

      (60.8, 70.7)
      7.4

      (6.9, 7.9)
      81.9

      (78.7, 84.7)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      11.8

      (11.1, 12.6)
      93.8

      (92.1, 95.2)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Diabetes7.3

      (7.0, 7.5)
      85.8

      (84.3, 87.1)
      3.3

      (3.0, 3.5)
      76.0

      (72.2, 79.4)
      11.8

      (11.2, 12.5)
      85.4

      (82.9, 87.5)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      12.6

      (11.8, 13.3)
      93.2

      (91.3, 94.7)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Cancers1.7

      (1.6, 1.9)
      85.9

      (82.6, 88.7)
      0.6

      (0.5, 0.7)
      64.6

      (54.4, 73.6)
      2.5

      (2.2, 2.9)
      82.4

      (75.6, 87.7)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      3.9

      (3.5, 4.4)
      96.0

      (94.1, 97.3)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Chronic kidney disease0.4

      (0.4, 0.5)
      86.3

      (79.4, 91.2)
      0.2

      (0.1, 0.2)
      62.7

      (43.7, 78.5)
      0.6

      (0.4, 0.8)
      93.6

      (87.5, 96.9)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      0.9

      (0.7, 1.2)
      92.0

      (83.1, 96.4)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Liver disease0.3

      (0.2, 0.3)
      78.9

      (69.4, 86.1)
      0.2

      (0.1, 0.3)
      76.5

      (61.2, 87.1)
      0.4

      (0.3, 0.6)
      71.4

      (51.1, 85.7)
      0.4

      (0.3, 0.5)
      88.2

      (73.5, 95.2)
      Overweight2.1

      (2.0, 2.3)
      88.9

      (86.4, 91.1)
      2.1

      (2.0, 2.3)
      86.6

      (82.5, 89.9)
      2.7

      (2.4, 3.0)
      93.4

      (90.2, 95.6)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      1.6

      (1.4, 1.9)
      88.9

      (81.8, 93.5)
      Sickle cell disease0.1

      (0.1, 0.1)
      64.7

      (48.3, 78.3)
      0.1

      (0.1, 0.1)
      63.7

      (39.7, 82.3)
      0.1

      (0.1, 0.2)
      63.4

      (32.9, 85.9)
      0.1

      (0.1, 0.2)
      Cells with denominator n<30 are suppressed. COPD, chronic obstructive pulmonary disease; NA, not applicable; NIS-ACM, National Immunization Survey-Adult COVID Module.
      Smoking0.5

      (0.4, 0.6)
      80.1

      (73.6, 85.3)
      0.4

      (0.4, 0.5)
      71.9

      (61.2, 80.5)
      0.7

      (0.6, 1.0)
      86.4

      (78.2, 91.9)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      0.4

      (0.3, 0.6)
      90.5

      (76.5, 96.6)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Organ or blood transplant0.1

      (0.1, 0.1)
      80.5

      (63.1, 90.9)
      0.0

      (0.0, 0.1)
      58.8

      (28.3, 83.7)
      0.1

      (0.1, 0.2)
      87.4

      (71.8, 95.0)
      0.2

      (0.1, 0.3)
      89.6

      (52.8, 98.5)
      Stroke or cerebrovascular disease0.2

      (0.1, 0.2)
      83.8

      (73.2, 90.7)
      0.1

      (0.0, 0.1)
      87.1

      (62.4, 96.5)
      0.2

      (0.1, 0.3)
      76.0

      (59.0, 87.4)
      0.4

      (0.3, 0.6)
      87.5

      (66.2, 96.2)
      Dementia or other neurologic conditions0.1

      (0.1, 0.2)
      76.8

      (61.7, 87.2)
      0.1

      (0.0, 0.1)
      75.1

      (48.3, 90.7)
      0.2

      (0.1, 0.3)
      62.0

      (38.5, 80.9)
      0.2

      (0.1, 0.4)
      95.7

      (81.4, 99.1)
      Immunocompromised state2.0

      (1.8, 2.1)
      76.7

      (73.1, 80.0)
      1.8

      (1.6, 1.9)
      65.1

      (59.5, 70.3)
      2.6

      (2.3, 3.0)
      83.9

      (77.5, 88.7)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      1.8

      (1.5, 2.1)
      94.0

      (88.9, 96.8)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      HIV infection0.1

      (0.1, 0.2)
      87.0

      (77.2, 92.9)
      0.1

      (0.1, 0.1)
      66.9

      (47.9, 81.6)
      0.3

      (0.2, 0.4)
      97.1

      (86.7, 99.4)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      0.1

      (0.1, 0.3)
      97.6

      (90.0, 99.5)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      PregnantNA61.2

      (48.8, 72.3)
      0.3

      (0.2, 0.4)
      60.4

      (47.9, 71.6)
      NANANANA
      Other conditions4.8

      (4.5, 5.0)
      77.9

      (75.7, 80.0)
      3.7

      (3.4, 4.0)
      66.6

      (62.6, 70.3)
      6.2

      (5.8, 6.7)
      81.3

      (77.7, 84.5)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      6.0

      (5.5, 6.5)
      92.1

      (89.2, 94.3)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      ≥1 high-risk condition28.3

      (27.9, 28.8)
      81.8

      (80.9, 82.6)
      19.2

      (18.7, 19.8)
      70.9

      (69.2, 72.4)
      37.9

      (36.9, 38.8)
      83.8

      (82.4, 85.1)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      41.0

      (39.9, 42.1)
      92.8

      (91.8, 93.7)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      No high-risk conditions71.7

      (71.2, 72.1)
      70.3

      (69.7, 70.9)
      80.8

      (80.2, 81.3)
      62.1

      (61.3, 62.9)
      62.1

      (61.2, 63.1)
      78.3

      (77.1, 79.4)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      59.0

      (57.9, 60.1)
      90.4

      (89.4, 91.3)
      p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      Note: Boldface indicates statistical significance (p<0.05).
      a Weighted percentages.
      b Chronic lung disease includes COPD, asthma (moderate to severe), interstitial lung disease, cystic fibrosis, and pulmonary hypertension.
      c Heart disease includes heart failure, coronary artery disease, cardiomyopathies, or hypertension.
      d p<0.05 by t test for comparisons of vaccination coverage between persons aged 18–49 years and persons aged 50–64 years and persons aged 18–49 years and persons aged ≥65 years within each level of each characteristic.
      e Cells with denominator n<30 are suppressed.COPD, chronic obstructive pulmonary disease; NA, not applicable; NIS-ACM, National Immunization Survey-Adult COVID Module.
      COVID-19 vaccination coverage was highest among adults aged ≥18 years with reported high-risk medical conditions and who also reported that they were overweight (88.9%), followed by those who had HIV infection (87.0%), chronic kidney disease (86.3%), cancers (85.9%), diabetes (85.8%), heart diseases (83.9%), and stroke or cerebrovascular disease (83.8%); had received an organ or blood transplant (80.5%); were smokers (80.1%); who had liver disease (78.9%), chronic lung disease (78.6%), and dementia or other neurologic conditions (76.8%); were immunocompromised (76.7%); and had sickle cell disease (64.7%) (Table 3).

      DISCUSSION

      COVID-19 vaccination coverage was higher among adults with reported high-risk medical conditions than among those who did not report these conditions, possibly owing to the ACIP recommendation to prioritize persons at high risk of severe illness from COVID-19 for vaccination early in the vaccination program and public health messaging emphasizing the importance of COVID-19 vaccines for persons with increased risk of severe COVID-19.
      • Dooling K
      • Marin M
      • Wallace M
      • et al.
      The Advisory Committee on Immunization Practices’ updated interim recommendation for allocation of COVID-19 vaccine - United States, December 2020.
      However, by late summer 2021, about 18.0% of adults with reported high-risk medical conditions still had not received ≥1 dose of a COVID-19 vaccine even though they were less likely to report “probably will not or definitely will not get vaccinated” than those who did not report these conditions. With another 9.2% reporting that they still planned to get vaccinated or were unsure, vaccination coverage might improve and reach 90.0%. Public health messaging to make people aware of their risk status is especially important given that most COVID-19 vaccines were not administered by a person's primary healthcare provider.
      Adults with reported high-risk medical conditions reported more positive attitudes toward vaccination than those who did not report these conditions. Higher levels of concern about COVID-19 and positive attitudes toward vaccination among adults with reported high-risk medical conditions (e.g., more likely to report believing that COVID-19 vaccines are safe and important for protection from COVID-19 infection) may contribute to higher vaccination coverage among those with reported high-risk medical conditions. A larger number of unvaccinated adults with reported high-risk medical conditions reported difficulties in getting a COVID-19 vaccine (e.g., difficulty in getting an appointment online, difficulty in knowing where to get vaccinated, difficulty in getting to vaccination sites) than those without these conditions. Many of these barriers could be reduced if vaccinations could be provided in the office of their usual medical provider, however, the cold chain requirement for storing the vaccine might still be a challenge for implementing this effort. Reducing barriers to COVID-19 vaccination could improve vaccination coverage among adults with or without reported high-risk medical conditions. In addition, one study indicated that the most common reasons for not receiving COVID-19 vaccines were “concerned about possible side effects” and “don't trust the COVID-19 vaccine.”
      • Monte LM.
      Who are the adults not vaccinated against COVID?.
      Clear, consistent messages from healthcare providers, public health officials, and immunization partners about the safety and effectiveness of the vaccine could increase vaccination coverage and vaccine confidence more broadly.
      Building confidence in COVID-19 vaccines
      Centers for Disease Control and Prevention.
      Healthcare provider recommendation is significantly associated with vaccine uptake.
      • Lu PJ
      • Srivastav A
      • Amaya A
      • et al.
      Association of provider recommendation and offer and influenza vaccination among adults aged ≥18 years - United States.
      This report showed that COVID-19 vaccination coverage was significantly higher among adults aged ≥18 years with a provider recommendation for the vaccine than among those without, reinforcing the importance of provider recommendation on COVID-19 vaccination uptake. Providers should recommend the vaccination when they have the opportunity to do so. Patients usually trust the opinions of their healthcare providers regarding vaccination more than the opinions of others.
      • Lu PJ
      • Srivastav A
      • Amaya A
      • et al.
      Association of provider recommendation and offer and influenza vaccination among adults aged ≥18 years - United States.
      ,
      • Lu PJ
      • O'Halloran A
      • Ding H
      • Srivastav A
      • Williams WW.
      Uptake of influenza vaccination and missed opportunities among adults with high-risk conditions, United States, 2013.
      Clinicians and healthcare providers should follow ACIP recommendations,
      • Dooling K
      • Marin M
      • Wallace M
      • et al.
      The Advisory Committee on Immunization Practices’ updated interim recommendation for allocation of COVID-19 vaccine - United States, December 2020.
      recommend needed vaccinations, and encourage eligible persons to be fully vaccinated against COVID-19.
      Findings from this study showed that vaccination coverage among adults aged 50–64 and ≥65 years with reported high-risk medical conditions was significantly higher than among those aged 18–49 years with reported high-risk medical conditions. The risk for severe illness from COVID-19 increases with age, with older adults at the highest risk.
      • Kim L
      • Garg S
      • O'Halloran A
      • et al.
      Risk factors for intensive care unit admission and in-hospital mortality among hospitalized adults identified through the US coronavirus disease 2019 (COVID-19)-Associated Hospitalization Surveillance Network (COVID-NET).
      ,

      COVID-19 risks and vaccine information for older adults. Centers for Disease Control and Prevention. https://www.cdc.gov/aging/covid19/covid19-older-adults.html. Updated August 4, 2021. Accessed March 8, 2022.

      Higher COVID-19 vaccination coverage among older adults may also be owing to ACIP prioritization and recognition of the increased risk of severe COVID-19 in this population.
      • Dooling K
      • Marin M
      • Wallace M
      • et al.
      The Advisory Committee on Immunization Practices’ updated interim recommendation for allocation of COVID-19 vaccine - United States, December 2020.
      The higher prevalence of provider recommendation of COVID-19 vaccine among older adults from this study might also contribute to higher vaccination coverage among this group. Healthcare providers should ensure that persons at high risk receive COVID-19 vaccination if they are eligible regardless of age. Among adults with reported high-risk medical conditions, vaccination coverage was particularly low among adults living in poverty or without health insurance, and efforts are needed to continue to be made to reach these people and reduce inequities.
      • Lu PJ
      • O'Halloran A
      • Ding H
      • Srivastav A
      • Williams WW.
      Uptake of influenza vaccination and missed opportunities among adults with high-risk conditions, United States, 2013.
      ,
      • Lu PJ
      • Hung MC
      • O'Halloran AC
      • et al.
      Seasonal influenza vaccination coverage trends among adult populations, U.S., 2010–2016.
      ,
      • Lu PJ
      • Hung MC
      • Srivastav A
      • et al.
      Surveillance of vaccination coverage among adult populations -United States, 2018.
      COVID-19 vaccination coverage varied substantially by type of reported high-risk medical conditions. Lower COVID-19 vaccination coverage for adults reporting sickle cell disease, liver disease, dementia, or other neurologic conditions and for those who were immunocompromised is concerning, and intervention and education efforts targeting individual groups where vaccination coverage is low may be beneficial. Adults with sickle cell disease, liver disease, dementia, or other neurologic conditions and those who are immunocompromised are often in the care of subspecialists, so it is important for subspecialists to recommend vaccines to these patients even if they are not vaccine providers themselves. In addition, some adults may not consider themselves at increased risk for severe COVID-19; the messaging might need to be tailored differently for these groups.
      • Lu PJ
      • O'Halloran A
      • Ding H
      • Srivastav A
      • Williams WW.
      Uptake of influenza vaccination and missed opportunities among adults with high-risk conditions, United States, 2013.

      Limitations

      Several limitations should be considered when interpreting these findings. First, NIS-ACM has a low response rate (20.5% in August and 20.9% in September) but is consistent with other National Immunization Survey surveys.
      About the National immunization surveys (NIS).
      Second, COVID-19 vaccination was self-reported and may be subject to recall or social desirability bias. However, because vaccines have been available for about 6 months at the time the survey was conducted, the reliability of self-reported COVID-19 vaccination may be comparable with that of self-report of influenza vaccination for current or recent seasons, which has been shown to have a relatively high agreement with vaccination status ascertained from medical records.
      • Rolnick SJ
      • Parker ED
      • Nordin JD
      • et al.
      Self-report compared to electronic medical record across eight adult vaccines: do results vary by demographic factors?.
      ,
      • King JP
      • McLean HQ
      • Belongia EA.
      Validation of self-reported influenza vaccination in the current and prior season.
      Moreover, survey weights were calibrated to COVID-19 vaccine administration data to mitigate possible bias from incomplete sample frame, nonresponse, and misclassification of vaccination status. Third, the question on medical conditions could have been interpreted by some survey respondents as medical conditions that place them at higher risk for exposure to COVID-19; however, a secondary analysis found that approximately 75% of conditions reported by those who identified themselves in this survey as having a condition that puts them at higher risk of COVID-19 were among the conditions recognized by the ACIP as increasing one's risk of severe COVID-19 disease. Furthermore, coverage among insured adults who reported having conditions that put them at increased risk of COVID-19 on the basis of this study (82.9%) matched well with an estimate of coverage among insured adults with medical conditions based on data from 8 integrated healthcare organizations as of September (84.0%) (CDC unpublished data). In addition, medical conditions were self-reported, but self-reported medical conditions have been shown to have a relatively high agreement compared with medical records.
      • Martin LM
      • Leff M
      • Calonge N
      • Garrett C
      • Nelson DE.
      Validation of self-reported chronic conditions and health services in a managed care population.
      Finally, provider recommendation of the COVID-19 vaccine was self-reported and may be subject to recall bias.

      CONCLUSIONS

      COVID-19 vaccination coverage among adults with reported high-risk medical conditions varied substantially by medical condition and remains suboptimal. Higher COVID-19 vaccination coverage in those with reported high-risk medical conditions may be owing to ACIP prioritization and recognition of the increased risk of severe COVID-19 in persons who reported these medical conditions. Even among this group that recognized themselves as high risk, vaccination can be improved, with 82.0% vaccinated and another 9.0% planning or unsure about getting vaccinated. Clinicians and other healthcare providers, such as pharmacists and clinical subspecialists, can educate and encourage everyone, especially older people, to be fully vaccinated against COVID-19.

      Underlying medical conditions associated with high risk for severe COVID-19: information for healthcare providers. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-care/underlyingconditions.html. Updated June 15, 2022. Accessed March 8, 2022.

      CDC resources are available for building vaccine confidence in the community.
      Building confidence in COVID-19 vaccines
      Centers for Disease Control and Prevention.

      COVID-19 vaccine equity for racial and ethnic minority groups. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/community/health-equity/vaccine-equity.html. Updated March 29, 2022. Accessed January 14, 2022.

      As of April 21, 2022, ACIP has recommended that immunocompromised people who received a 2-dose series of mRNA (or 1 dose of Janssen) COVID-19 vaccine receive an additional primary dose of mRNA (or Janssen) COVID-19 vaccine because studies indicate a reduced antibody response in immunocompromised people after a primary vaccine series compared with that in healthy vaccine recipients.

      Interim clinical considerations for use of COVID-19 vaccines currently approved or authorized in the United States. Centers for Disease Control and Prevention. https://www.cdc.gov/vaccines/covid-19/clinical-considerations/interim-considerations-us.html#appendix-d. Updated June 30, 2022. Accessed May 4, 2022.

      ,
      Centers for Disease Control and Prevention
      Data and clinical considerations for additional doses in immunocompromised people.
      Adults with high-risk medical conditions have been recommended to receive a booster dose 6 months after the primary series of mRNA vaccines or 2 or more months after Janssen vaccine.

      CDC statement on ACIP booster recommendations. Centers for Disease Control and Prevention. https://www.cdc.gov/media/releases/2021/p0924-booster-recommendations-.html. Updated September 24, 2021. Accessed March 8, 2022.

      ,

      CDC Expands eligibility for COVID-19 booster shots. Centers for Disease Control and Prevention. https://www.cdc.gov/media/releases/2021/p1021-covid-booster.html. Updated October 21, 2021. Accessed March 8, 2022.

      Continual monitoring of primary, additional (among immunocompromised), and booster dose vaccination will be helpful for developing tailored strategies to improve vaccination coverage among this high-risk population.

      CRediT AUTHOR STATEMENT

      Peng-jun Lu: Conceptualization, Methodology, Writing - original draft. Mei-Chuan Hung: Conceptualization, Formal analysis. Hannah L. Jackson: Conceptualization, Writing - review and editing. Jennifer L. Kriss: Conceptualization, Writing - review and editing. Anup Srivastav: Conceptualization, Formal analysis. David Yankey: Conceptualization, Methodology. Tammy A. Santibanez: Conceptualization, Writing - review and editing. James Tseryuan Lee: Conceptualization, Writing - review and editing. Lu Meng: Conceptualization, Writing - review and editing. Hilda Razzaghi: Conceptualization, Writing - review and editing. Carla L. Black: Conceptualization, Writing - review and editing. Laurie D. Elam-Evans: Conceptualization, Investigation, Writing - review and editing. James A. Singleton: Conceptualization, Investigation, Methodology, Supervision, Writing – review and editing.

      ACKNOWLEDGMENTS

      The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
      No financial disclosures were reported by the authors of this paper.

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