Brief report| Volume 43, ISSUE 3, P282-292, September 01, 2012

# H1N1 and Seasonal Influenza Vaccination of U.S. Healthcare Personnel, 2010

### Background

Seasonal influenza vaccination routinely has been recommended for healthcare personnel (HCP) since 1984. The influenza A (H1N1) 2009 monovalent vaccine (H1N1 vaccine) became available in the U.S. in October 2009.

### Purpose

To assess 2009 H1N1 and seasonal influenza vaccination coverage and identify factors independently associated with vaccination among HCP in the U.S.

### Methods

Data from the 2009–2010 Behavioral Risk Factor Surveillance System (BRFSS) influenza supplemental survey were analyzed in 2011. Multivariable logistic regression and predictive marginal models were performed to identify factors independently associated with vaccination among HCP. The Kaplan-Meier survival analysis procedure was used to estimate the cumulative proportion of people vaccinated.

### Results

Among 16,975 HCP surveyed, 2009 H1N1, seasonal, and any-dose vaccination coverage were 34.1% (95% CI=32.7%, 35.5%); 52.4% (95% CI=50.9%, 53.9%); and 58.0% (95% CI=56.5%, 59.5%), respectively, all of which were significantly higher than those for non-HCP (19.1%, 34.9%, and 40.3%, respectively). The H1N1 vaccination coverage among HCP ranged from 18.4% in Mississippi to 56.1% in Massachusetts and seasonal influenza vaccination coverage ranged from 40.4% in Florida to 73.1% in Nebraska. Characteristics independently associated with an increased likelihood of 2009 H1N1, seasonal, and any-dose vaccinations among HCP were as follows: non-Hispanic white, higher income, having a high-risk condition, having health insurance, the ability to see a doctor if needed, and having had a routine checkup in the previous year.

### Conclusions

Vaccination coverage was higher among HCP than non-HCP but still below the national health objective of 90%. Knowledge of national and state-specific H1N1 and seasonal vaccination coverage among HCP is useful for evaluating the vaccination campaign and implementing strategies for increasing yearly seasonal vaccination coverage and improving vaccination coverage among HCP in possible future pandemics.

## Introduction

Healthcare personnel (HCP) can acquire influenza from patients or transmit influenza to patients.
CDC
Immunization of health-care workers: recommendations of the Advisory Committee on Immunization Practices (ACIP) and the Hospital Infection Control Practices Advisory Committee (HICPAC).
CDC
Influenza vaccination of health-care personnel.
Vaccination of HCP for influenza is important to reduce transmission of influenza in healthcare settings.
CDC
Influenza vaccination of health-care personnel.
Influenza outbreaks in hospitals and long-term care settings have been associated with low vaccination coverage among HCP.
CDC
Influenza vaccination of health-care personnel.
• Potter J.
• Stott D.J.
• Roberts M.A.
• et al.
Influenza vaccination of health care workers in long-term-care hospitals reduces the mortality of elderly patients.
• Giannetta E.T.
• Hayden F.G.
• Farr B.M.
Preventing nosocomial influenza by improving the vaccine acceptance rate of clinicians.
Annual influenza vaccination has been recommended by the Advisory Committee on Immunization Practices (ACIP) for HCP since 1984.
CDC
Prevention and control of influenza.
In April 2009, a novel influenza A (H1N1) virus emerged in the U.S., and within weeks it had spread to every region in the country.
CDC
Use of influenza A (H1N1) 2009 monovalent vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009.
In July 2009, the ACIP issued recommendations regarding the use of a new monovalent vaccine against infection with the 2009 influenza A (H1N1) virus.
CDC
Use of influenza A (H1N1) 2009 monovalent vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009.
HCP was one of five initial target groups to be recommended to receive the influenza A (H1N1) 2009 monovalent vaccine (2009 H1N1 vaccine) when it became available in October 2009.
CDC
Use of influenza A (H1N1) 2009 monovalent vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009.
The current study mainly addresses and examines the following questions: (1) What is the national 2009 H1N1, seasonal, and any-dose vaccination coverage (seasonal and/or H1N1) among HCP and non-HCP? (2) What are state-specific vaccination levels among HCP and non-HCP? Do state-specific vaccination levels among HCP vary? (3) What factors affect vaccination coverage among HCP and non-HCP?

## Methods

Data from the 2009–2010 BRFSS influenza supplemental survey collected from March through June 2010 were used for national analysis. Influenza vaccination data were not collected for Delaware and Vermont. The BRFSS is a continuous, population-based telephone survey coordinated by state health departments in collaboration with the CDC.
CDC
2009 BRFSS Summary Data Quality Report.
Point estimates and 95% CIs were calculated using SUDAAN, version 10.01. The following method was used to calculate vaccination coverage in both bivariate and multivariable analyses. For the estimate of national H1N1 vaccination coverage during the 2009–2010 season, only individuals who were interviewed March 2010–June 2010 and vaccinated October 2009–February 2010 were included. For the estimate of national seasonal vaccination coverage during the 2009–2010 season, only individuals interviewed March 2010–June 2010 and vaccinated August 2009–February 2010 were included. To increase sample size and get reliable state-specific H1N1 and seasonal influenza vaccination coverage, the cumulative proportion of people vaccinated during the 2009–2010 season was used in the Kaplan-Meier survival analysis procedure. Multivariable analyses using logistic regression models were performed between HCP and non-HCP to get adjusted percentages.
• Korn E.L.
• Graubard B.I.
Predictive margins (direct standardization).
• Shapiro J.A.
• Klabunde C.N.
• et al.
A national survey of primary care physicians' methods for screening for fecal occult blood.

## Results

Of the 130,774 adults, 12.3% (16,975) were HCP. Of those who worked within the healthcare setting, 41.3% had no direct patient contact and 58.7% had direct patient contact. Overall, H1N1, seasonal, and any-dose vaccination coverage were 34.1%, 52.4%, and 58.0%, respectively, which were higher than those for non-HCP (19.1%, 34.9%, and 40.3%, respectively). Across the majority of subgroups, H1N1, seasonal, and any-dose vaccination coverage were higher among HCP compared with non-HCP (Table 1). H1N1, seasonal, and any-dose vaccination coverage among HCP with direct patient contact were 38.1%, 55.8%, and 61.6%, respectively (data not shown), which were significantly higher than those for HCP.
Table 1H1N1 and seasonal influenza vaccination coverage by demographic and access-to-care variables among those aged ≥18 years, BRFSS 2010, % (95% CI)
DEMOGRAPHICH1N1 vaccination coverageSeasonal influenza vaccination coverageAny influenza vaccination coverage (seasonal and/or H1N1)
Healthcare personnelNon–healthcare personnelHealthcare personnelNon–healthcare personnelHealthcare personnelNon–healthcare personnel
Total34.1 (32.7, 35.5)19.1 (18.7, 19.6)
p<0.05 by t-test for comparisons between HCP and non-HCP
52.4 (50.9, 53.9)34.9 (34.4, 35.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
58.0 (56.5, 59.5)40.3 (39.7, 40.9)
p<0.05 by t-test for comparisons between HCP and non-HCP
Age (years)
18–49
Reference level
33.7 (31.7, 35.7)16.3 (15.6, 17.0)
p<0.05 by t-test for comparisons between HCP and non-HCP
48.0 (45.8, 50.2)23.9 (23.2, 24.7)
p<0.05 by t-test for comparisons between HCP and non-HCP
54.3 (52.1, 56.5)30.1 (29.2, 31.0)
p<0.05 by t-test for comparisons between HCP and non-HCP
50–6435.0 (32.9, 37.1)20.0 (19.3, 20.7)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
54.7 (52.6, 56.9)
p<0.05 by t-test for comparisons within each variable with indicated reference level
39.4 (38.5, 40.2)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
59.2 (57.1, 61.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
43.8 (42.9, 44.7)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
≥6534.6 (32.1, 37.1)27.2 (26.4, 27.9)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
70.1 (67.7, 72.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
64.2 (63.4, 65.0)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
74.3 (71.9, 76.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
68.4 (67.7, 69.2)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
Gender
Male
Reference level
37.2 (34.3, 40.3)18.7 (18.0, 19.4)
p<0.05 by t-test for comparisons between HCP and non-HCP
50.2 (47.1, 53.3)32.6 (31.8, 33.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
57.9 (54.8, 60.9)37.8 (37.0, 38.8)
p<0.05 by t-test for comparisons between HCP and non-HCP
Female32.8 (31.3, 34.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
19.6 (19.1, 20.2)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
53.3 (51.6, 55.0)37.3 (36.7, 38.0)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
58.1 (56.3, 59.8)42.9 (42.2, 43.6)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
Race/ethnicity
White, non-Hispanic
Reference level
37.3 (35.8, 38.8)19.7 (19.2, 20.1)
p<0.05 by t-test for comparisons between HCP and non-HCP
56.9 (55.3, 58.5)38.7 (38.1, 39.3)
p<0.05 by t-test for comparisons between HCP and non-HCP
62.3 (60.7, 63.9)43.2 (42.6, 43.8)
p<0.05 by t-test for comparisons between HCP and non-HCP
Black, non-Hispanic21.7 (18.6, 25.2)
p<0.05 by t-test for comparisons within each variable with indicated reference level
15.4 (13.9, 17.1)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
39.4 (35.2, 43.7)
p<0.05 by t-test for comparisons within each variable with indicated reference level
27.6 (25.7, 29.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
43.9 (39.6, 48.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
33.1 (31.1, 35.1)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
Hispanic27.7 (22.9, 33.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
18.5 (16.9, 20.3)
p<0.05 by t-test for comparisons between HCP and non-HCP
44.4 (38.7, 50.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
23.5 (21.8, 25.2)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
49.7 (43.9, 55.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
32.1 (30.1, 34.1)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
Other36.7 (30.7, 43.1)20.4 (18.5, 22.4)
p<0.05 by t-test for comparisons between HCP and non-HCP
47.6 (41.1, 54.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
32.1 (29.8, 34.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
56.6 (49.6, 63.3)39.3 (36.8, 41.8)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
Education level
Less than high school
Reference level
23.0 (17.8, 29.2)18.1 (16.7, 19.5)38.4 (32.2, 45.1)27.8 (26.3, 29.3)
p<0.05 by t-test for comparisons between HCP and non-HCP
46.8 (40.0, 53.8)35.8 (34.1, 37.6)
p<0.05 by t-test for comparisons between HCP and non-HCP
High school graduate24.2 (21.7, 26.9)17.0 (16.2, 17.9)
p<0.05 by t-test for comparisons between HCP and non-HCP
44.2 (41.1, 47.3)33.4 (32.4, 34.4)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
50.5 (47.3, 53.6)38.4 (37.4, 39.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
College38.6 (37.0, 40.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
20.9 (20.3, 21.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
56.5 (54.8, 58.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
37.9 (37.2, 38.6)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
61.7 (59.9, 63.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
42.8 (42.0, 43.5)
p<0.05 by t-test for comparisons between HCP and non-HCP
,
p<0.05 by t-test for comparisons within each variable with indicated reference level
Income ($) <20,000 Reference level 21.8 (18.1, 26.0)17.5 (16.5, 18.6) p<0.05 by t-test for comparisons between HCP and non-HCP 38.6 (33.9, 43.6)29.0 (27.8, 30.2) p<0.05 by t-test for comparisons between HCP and non-HCP 43.7 (38.9, 48.7)35.6 (34.2, 37.0) p<0.05 by t-test for comparisons between HCP and non-HCP 20,000–50,00029.3 (27.0, 31.6) p<0.05 by t-test for comparisons within each variable with indicated reference level 18.5 (17.7, 19.4) p<0.05 by t-test for comparisons between HCP and non-HCP 47.8 (45.2, 50.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 35.2 (34.2, 36.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 54.0 (51.4, 56.6) p<0.05 by t-test for comparisons within each variable with indicated reference level 40.2 (39.1, 41.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level ≥50,00042.1 (40.0, 44.2) p<0.05 by t-test for comparisons within each variable with indicated reference level 20.5 (19.8, 21.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 60.8 (58.6, 62.9) p<0.05 by t-test for comparisons within each variable with indicated reference level 37.3 (36.4, 38.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 65.8 (63.6, 67.9) p<0.05 by t-test for comparisons within each variable with indicated reference level 40.2 (39.1, 41.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level Marital status Married Reference level 37.9 (36.2, 39.6)20.2 (19.7, 20.8) p<0.05 by t-test for comparisons between HCP and non-HCP 57.0 (55.2, 58.8)37.0 (36.3, 37.7) p<0.05 by t-test for comparisons between HCP and non-HCP 62.8 (61.0, 64.5)42.2 (41.5, 42.9) p<0.05 by t-test for comparisons between HCP and non-HCP Widowed/divorced/separated29.1 (26.3, 31.9) p<0.05 by t-test for comparisons within each variable with indicated reference level 19.1 (18.3, 19.9) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 51.1 (48.0, 54.1) p<0.05 by t-test for comparisons within each variable with indicated reference level 41.6 (40.6, 42.7) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 55.2 (52.1, 58.3) p<0.05 by t-test for comparisons within each variable with indicated reference level 46.3 (45.3, 47.4) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level Never married28.0 (24.5, 31.8) p<0.05 by t-test for comparisons within each variable with indicated reference level 16.2 (15.0, 17.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 40.2 (36.1, 44.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 23.2 (21.8, 24.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 46.4 (42.1, 50.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 29.6 (28.0, 31.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level Perceived health Excellent/very good Reference level 35.7 (33.9, 37.6)18.3 (17.7, 19.0) p<0.05 by t-test for comparisons between HCP and non-HCP 53.1 (51.1, 55.0)32.9 (32.1, 33.7) p<0.05 by t-test for comparisons between HCP and non-HCP 58.3 (56.3, 60.3)38.1 (37.3, 39.0) p<0.05 by t-test for comparisons between HCP and non-HCP Good31.3 (28.8, 33.8) p<0.05 by t-test for comparisons within each variable with indicated reference level 18.4 (17.7, 19.2) p<0.05 by t-test for comparisons between HCP and non-HCP 51.0 (48.1, 53.9)34.2 (33.2, 35.1) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 56.1 (53.3, 58.9)39.5 (38.4, 40.5) p<0.05 by t-test for comparisons between HCP and non-HCP Fair34.4 (30.2, 38.9)21.4 (20.2, 22.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 53.3 (48.8, 57.7)40.3 (38.8, 41.8) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 62.7 (58.3, 66.8)45.9 (44.3, 47.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level Poor30.7 (20.4, 43.4)25.3 (23.4, 27.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 51.5 (41.3, 61.5)45.1 (42.9, 47.2) p<0.05 by t-test for comparisons within each variable with indicated reference level 57.5 (47.4, 67.0)51.2 (49.0, 53.4) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level People with high-risk conditions Yes37.2 (34.3, 40.2)26.0 (25.1, 27.0) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 60.8 (57.6, 63.9) p<0.05 by t-test for comparisons within each variable with indicated reference level 49.4 (48.4, 50.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 65.9 (62.7, 69.0) p<0.05 by t-test for comparisons within each variable with indicated reference level 55.1 (54.0, 56.1) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level No Reference level 33.2 (31.7, 34.8)16.7 (16.2, 17.2) p<0.05 by t-test for comparisons between HCP and non-HCP 49.8 (48.1, 51.5)29.8 (29.2, 30.5) p<0.05 by t-test for comparisons between HCP and non-HCP 55.6 (53.8, 57.3)35.1 (34.4, 35.8) p<0.05 by t-test for comparisons between HCP and non-HCP Insurance status Yes37.3 (35.8, 38.8) p<0.05 by t-test for comparisons within each variable with indicated reference level 21.1 (20.6, 21.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 56.9 (55.3, 58.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 39.6 (39.0, 40.2) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 62.6 (61.0, 64.2) p<0.05 by t-test for comparisons within each variable with indicated reference level 45.0 (44.4, 45.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level No Reference level 15.1 (12.5, 18.1)10.3 (9.4, 11.3) p<0.05 by t-test for comparisons between HCP and non-HCP 25.5 (22.0, 29.4)14.0 (13.0, 15.1) p<0.05 by t-test for comparisons between HCP and non-HCP 29.8 (26.1, 33.8)19.2 (18.0, 20.5) p<0.05 by t-test for comparisons between HCP and non-HCP Need to see a doctor but could not Yes Reference level 18.7 (16.1, 21.7)12.8 (11.8, 13.9) p<0.05 by t-test for comparisons between HCP and non-HCP 33.1 (29.5, 37.0)20.3 (19.1, 21.6) p<0.05 by t-test for comparisons between HCP and non-HCP 39.0 (35.2, 42.9)25.6 (24.3, 27.0) p<0.05 by t-test for comparisons between HCP and non-HCP No37.3 (35.8, 38.9) p<0.05 by t-test for comparisons within each variable with indicated reference level 20.4 (19.9, 20.9) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 56.4 (54.7, 58.0) p<0.05 by t-test for comparisons within each variable with indicated reference level 37.9 (37.3, 38.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 61.9 (60.2, 63.5) p<0.05 by t-test for comparisons within each variable with indicated reference level 43.3 (42.6, 43.9) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level Primary doctor Yes36.1 (34.7, 37.6) p<0.05 by t-test for comparisons within each variable with indicated reference level 21.4 (20.9, 21.9) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 55.9 (54.3, 57.5) p<0.05 by t-test for comparisons within each variable with indicated reference level 40.4 (39.7, 41.0) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 61.4 (59.8, 63.0) p<0.05 by t-test for comparisons within each variable with indicated reference level 45.8 (45.1, 46.4) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level No Reference level 22.0 (18.8, 25.7)10.7 (9.7, 11.7) p<0.05 by t-test for comparisons between HCP and non-HCP 31.5 (27.5, 35.6)14.3 (13.3, 15.4) p<0.05 by t-test for comparisons between HCP and non-HCP 37.6 (33.4, 42.1)19.5 (18.3, 20.8) p<0.05 by t-test for comparisons between HCP and non-HCP Activity limitation Yes33.8 (30.7, 37.1)22.2 (21.4, 23.1) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 55.1 (51.6, 58.4)43.7 (42.6, 44.8) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 61.0 (57.6, 64.3)48.4 (47.3, 49.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level No Reference level 34.2 (32.7, 35.8)18.2 (17.7, 18.8) p<0.05 by t-test for comparisons between HCP and non-HCP 51.8 (50.1, 53.5)32.4 (31.8, 33.0) p<0.05 by t-test for comparisons between HCP and non-HCP 57.3 (55.6, 59.0)37.9 (37.3, 38.6) p<0.05 by t-test for comparisons between HCP and non-HCP Time since last checkup (years) <137.6 (36.0, 39.3) p<0.05 by t-test for comparisons within each variable with indicated reference level 23.1 (22.5, 23.7) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 58.7 (57.0, 60.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 43.0 (42.3, 43.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 64.1 (62.4, 65.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 48.8 (48.1, 49.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level ≥1 Reference level 26.6 (24.2, 29.1)11.6 (11.0, 12.3) p<0.05 by t-test for comparisons between HCP and non-HCP 38.0 (35.3, 40.8)20.0 (19.2, 20.8) p<0.05 by t-test for comparisons between HCP and non-HCP 44.2 (41.3, 47.2)24.4 (23.5, 25.3) p<0.05 by t-test for comparisons between HCP and non-HCP Smoking status Current smoker Reference level 27.8 (24.4, 31.5)12.9 (11.9, 14.0) p<0.05 by t-test for comparisons between HCP and non-HCP 42.7 (39.0, 46.5)23.7 (22.6, 24.8) p<0.05 by t-test for comparisons between HCP and non-HCP 49.5 (45.8, 53.3)28.0 (26.7, 29.3) p<0.05 by t-test for comparisons between HCP and non-HCP Former smoker38.8 (36.0, 41.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 22.6 (21.8, 23.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 60.3 (57.4, 63.2) p<0.05 by t-test for comparisons within each variable with indicated reference level 44.1 (43.1, 45.1) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 65.8 (62.9, 68.6) p<0.05 by t-test for comparisons within each variable with indicated reference level 49.0 (48.0, 50.0) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level Never smoked34.3 (32.5, 36.1) p<0.05 by t-test for comparisons within each variable with indicated reference level 19.8 (19.2, 20.5) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 52.4 (50.4, 54.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 34.8 (34.1, 35.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level 57.7 (55.7, 59.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 40.8 (40.0, 41.6) p<0.05 by t-test for comparisons between HCP and non-HCP , p<0.05 by t-test for comparisons within each variable with indicated reference level MSA In MSA34.0 (32.5, 35.5)19.2 (18.7, 19.7) p<0.05 by t-test for comparisons between HCP and non-HCP 52.3 (50.7, 53.9)35.0 (34.4, 35.6) p<0.05 by t-test for comparisons between HCP and non-HCP 58.0 (56.4, 59.6)40.4 (39.8, 41.0) p<0.05 by t-test for comparisons between HCP and non-HCP Not in an MSA Reference level 35.7 (31.4, 40.2)18.5 (17.2, 19.9) p<0.05 by t-test for comparisons between HCP and non-HCP 53.2 (48.6, 57.8)34.0 (32.4, 35.6) p<0.05 by t-test for comparisons between HCP and non-HCP 57.7 (53.0, 62.3)39.5 (37.8, 41.3) p<0.05 by t-test for comparisons between HCP and non-HCP Note: This table is based on interviews conducted during March through June 2010 only. BRFSS, Behavioral Risk Factor Surveillance System, HCP, healthcare professional; MSA, metropolitan statistical area a p<0.05 by t-test for comparisons between HCP and non-HCP b Reference level c p<0.05 by t-test for comparisons within each variable with indicated reference level In univariate analysis, among HCP, H1N1, seasonal, and any-dose vaccination coverage were lower for non-Hispanic blacks (21.7%, 39.4%, and 43.9%, respectively) and Hispanics (27.7%, 44.4%, and 49.7%, respectively) compared to non-Hispanic whites (37.3%, 56.9%, and 62.3%, respectively; Table 1). H1N1 vaccination coverage among HCP was higher among those who reported being male, having higher education, having higher income, being married, having access to a primary care physician, formerly or never smoking, and having health insurance. Additionally, people who needed to see a doctor but could not, and those who had not had a routine checkup within the past 1 year were less likely to be vaccinated (Table 1). Factors associated with seasonal and any-dose vaccinations were similar to factors associated with H1N1 vaccination. Adjusted coverage estimates from the multivariable model did not differ greatly from the crude vaccination coverage. Overall, factors independently associated with H1N1, seasonal, and any-dose vaccinations were similar. Characteristics independently associated with an increased likelihood of H1N1, seasonal, and any-dose vaccinations among HCP were being non-Hispanic white, having higher income, having a high-risk condition, having health insurance, having the ability to see a doctor if needed, and having a routine checkup in the previous year (Table 2). Table 2Adjusted H1N1 and seasonal influenza vaccination coverage among people aged ≥18 years, BRFSS 2010, % (95% CI) DEMOGRAPHICH1N1 vaccination coverageSeasonal influenza vaccination coverageAny influenza vaccination coverage (seasonal and/or H1N1) Healthcare personnelNon–healthcare personnelHealthcare personnelNon–healthcare personnelHealthcare personnelNon–healthcare personnel Age (years) 18–49 Reference level 36.6 (34.4, 38.9)18.3 (17.5, 19.2)52.5 (50.2, 54.8)28.3 (27.4, 29.2)58.7 (56.4, 60.9)34.5 (33.5, 35.5) 50–6433.8 (31.6, 36.0)18.9 (18.1, 19.6)52.5 (50.2, 54.8)36.2 (35.2, 37.1) p<0.05 by t-test for comparisons within each variable with indicated reference level 57.2 (54.8, 59.5)40.8 (39.8, 41.8) p<0.05 by t-test for comparisons within each variable with indicated reference level ≥6530.8 (27.7, 33.9) p<0.05 by t-test for comparisons within each variable with indicated reference level 22.3 (21.4, 23.3) p<0.05 by t-test for comparisons within each variable with indicated reference level 64.0 (60.6, 67.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 54.1 (52.9, 55.4) p<0.05 by t-test for comparisons within each variable with indicated reference level 67.9 (64.6, 71.3) p<0.05 by t-test for comparisons within each variable with indicated reference level 58.7 (57.4, 60.0) p<0.05 by t-test for comparisons within each variable with indicated reference level Gender Male Reference level 37.7 (34.5, 40.8)19.5 (18.7, 20.2)51.2 (48.0, 54.4)34.4 (33.5, 35.3)58.9 (55.8, 62.0)39.6 (38.7, 40.6) Female34.1 (32.4, 35.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 19.1 (18.4, 19.7)54.8 (53.0, 56.7)36.0 (35.2, 36.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 59.4 (57.5, 61.2)41.2 (40.4, 42.0) p<0.05 by t-test for comparisons within each variable with indicated reference level Race/ethnicity White, non-Hispanic Reference level 36.8 (35.1, 38.5)18.9 (18.4, 19.4)55.8 (54.0, 57.7)36.1 (35.5, 36.8)61.2 (59.4, 63.1)40.7 (40.0, 41.4) Black, non-Hispanic25.8 (21.9, 29.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 15.3 (13.6, 17.0) p<0.05 by t-test for comparisons within each variable with indicated reference level 44.5 (39.9, 49.0) p<0.05 by t-test for comparisons within each variable with indicated reference level 29.8 (27.7, 31.8) p<0.05 by t-test for comparisons within each variable with indicated reference level 49.5 (44.9, 54.1) p<0.05 by t-test for comparisons within each variable with indicated reference level 34.5 (32.4, 36.7) p<0.05 by t-test for comparisons within each variable with indicated reference level Hispanic32.2 (26.7, 37.7)23.4 (21.2, 25.7) p<0.05 by t-test for comparisons within each variable with indicated reference level 52.3 (46.4, 58.2)33.9 (31.7, 36.1)56.8 (51.1, 62.6)42.4 (40.1, 44.8) Other38.9 (32.1, 45.7)21.3 (19.0, 23.6) p<0.05 by t-test for comparisons within each variable with indicated reference level 53.5 (46.7, 60.3)35.2 (32.6, 37.7)61.8 (55.3, 68.4)41.9 (39.3, 44.6) Education level Less than high school Reference level 31.9 (25.0, 38.7)18.1 (16.5, 19.8)50.6 (43.3, 57.9)30.7 (28.8, 32.5)57.3 (50.4, 64.2)37.8 (35.8, 39.9) High school graduate28.0 (24.8, 31.2)17.6 (16.6, 18.5)49.2 (45.6, 52.8)34.0 (32.9, 35.1) p<0.05 by t-test for comparisons within each variable with indicated reference level 55.6 (52.0, 59.1)39.1 (37.9, 40.2) College37.5 (35.7, 39.3)20.6 (19.9, 21.2) p<0.05 by t-test for comparisons within each variable with indicated reference level 55.4 (53.5, 57.4)36.7 (36.0, 37.5) p<0.05 by t-test for comparisons within each variable with indicated reference level 60.6 (58.7, 62.5)41.7 (40.9, 42.5) p<0.05 by t-test for comparisons within each variable with indicated reference level Income ($)
<20,000
Reference level
29.5 (24.2, 34.7)19.6 (18.2, 21.0)47.5 (41.9, 53.0)32.3 (30.8, 33.8)53.3 (48.0, 58.7)38.8 (37.2, 40.4)
20,000–50,00032.9 (30.3, 35.4)19.1 (18.2, 20.0)51.0 (48.3, 53.7)35.2 (34.2, 36.2)
p<0.05 by t-test for comparisons within each variable with indicated reference level
57.3 (54.7, 60.0)40.4 (39.3, 41.4)
≥50,00037.8 (35.5, 40.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
19.2 (18.4, 20.1)57.1 (54.6, 59.7)
p<0.05 by t-test for comparisons within each variable with indicated reference level
36.3 (35.3, 37.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
62.0 (59.5, 64.6)
p<0.05 by t-test for comparisons within each variable with indicated reference level
41.1 (40.0, 42.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
Marital status
Married
Reference level
35.9 (34.0, 37.8)19.7 (19.1, 20.4)54.8 (52.8, 56.8)35.8 (35.0, 36.5)61.0 (59.0, 63.0)41.0 (40.3, 41.8)
Widowed/divorced/separated34.7 (31.4, 38.0)17.6 (16.6, 18.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
53.8 (50.4, 57.1)34.6 (33.4, 35.7)57.8 (54.5, 61.2)39.3 (38.1, 40.6)
Never married33.0 (28.6, 37.5)19.7 (18.0, 21.4)50.2 (45.4, 55.0)33.7 (31.9, 35.6)55.0 (50.2, 59.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
39.3 (37.4, 41.2)
Perceived health
Excellent/very good
Reference level
35.0 (33.0, 37.0)18.9 (18.0, 19.7)53.3 (51.1, 55.5)34.5 (33.6, 35.4)58.5 (56.3, 60.8)39.8 (38.9, 40.8)
Good33.7 (31.0, 36.4)18.8 (17.9, 19.7)53.5 (50.6, 56.4)34.8 (33.8, 35.8)58.5 (55.7, 61.4)39.9 (38.8, 41.0)
Fair40.2 (35.0, 45.4)20.4 (19.0, 21.9)57.1 (52.2, 61.9)37.4 (35.8, 39.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
65.1 (60.4, 69.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
42.5 (40.7, 44.2)
p<0.05 by t-test for comparisons within each variable with indicated reference level
Poor39.0 (26.9, 51.2)22.4 (20.0, 24.7)
p<0.05 by t-test for comparisons within each variable with indicated reference level
56.6 (45.6, 67.7)38.1 (35.7, 40.6)
p<0.05 by t-test for comparisons within each variable with indicated reference level
62.6 (52.4, 72.9)43.7 (41.0, 46.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
People with high-risk conditions
Yes39.3 (35.9, 42.6)
p<0.05 by t-test for comparisons within each variable with indicated reference level
23.6 (22.4, 24.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
59.9 (56.3, 63.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
42.1 (40.9, 43.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
65.2 (61.5, 68.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
48.0 (46.7, 49.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
No
Reference level
33.8 (32.1, 35.5)17.5 (16.9, 18.1)51.7 (49.9, 53.5)32.5 (31.8, 33.2)57.3 (55.4, 59.1)37.6 (36.8, 38.3)
Insurance status
Yes36.3 (34.6, 38.0)
p<0.05 by t-test for comparisons within each variable with indicated reference level
19.8 (19.3, 20.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
55.2 (53.4, 57.0)
p<0.05 by t-test for comparisons within each variable with indicated reference level
36.2 (35.5, 36.9)
p<0.05 by t-test for comparisons within each variable with indicated reference level
61.1 (59.3, 62.9)
p<0.05 by t-test for comparisons within each variable with indicated reference level
41.5 (40.8, 42.2)
p<0.05 by t-test for comparisons within each variable with indicated reference level
No
Reference level
24.6 (19.9, 29.3)15.2 (13.6, 16.8)42.4 (37.0, 47.8)27.5 (25.6, 29.4)46.0 (40.6, 51.3)33.0 (31.0, 34.9)
Need to see a doctor but could not
Yes
Reference level
26.6 (22.3, 30.8)16.4 (14.9, 17.9)45.6 (40.7, 50.4)30.5 (28.8, 32.2)52.0 (47.3, 56.6)35.7 (33.9, 37.5)
No36.5 (34.8, 38.2)
p<0.05 by t-test for comparisons within each variable with indicated reference level
19.7 (19.1, 20.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
55.3 (53.5, 57.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
35.9 (35.2, 36.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
60.6 (58.8, 62.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
41.1 (40.4, 41.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
Primary doctor
Yes35.5 (33.9, 37.1)20.0 (19.4, 20.6)
p<0.05 by t-test for comparisons within each variable with indicated reference level
54.6 (52.8, 56.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
36.7 (36.0, 37.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
60.0 (58.2, 61.7)
p<0.05 by t-test for comparisons within each variable with indicated reference level
42.1 (41.3, 42.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
No
Reference level
32.3 (27.1, 37.4)14.8 (13.4, 16.3)47.8 (42.4, 53.2)25.9 (24.2, 27.6)54.2 (48.8, 59.6)31.4 (29.7, 33.2)
Activity limitation
Yes34.8 (31.4, 38.2)20.5 (19.4, 21.5)
p<0.05 by t-test for comparisons within each variable with indicated reference level
53.4 (49.8, 57.1)37.6 (36.3, 38.9)
p<0.05 by t-test for comparisons within each variable with indicated reference level
59.2 (55.7, 62.8)42.7 (41.4, 44.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
No
Reference level
35.2 (33.6, 36.9)18.9 (18.3, 19.5)53.8 (52.1, 55.6)34.4 (33.8, 35.1)59.2 (57.5, 61.0)39.7 (39.0, 40.4)
Time since last checkup (years)
<137.2 (35.3, 39.0)
p<0.05 by t-test for comparisons within each variable with indicated reference level
21.5 (20.8, 22.2)
p<0.05 by t-test for comparisons within each variable with indicated reference level
56.9 (55.0, 58.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
38.4 (37.6, 39.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
62.4 (60.5, 64.3)
p<0.05 by t-test for comparisons within each variable with indicated reference level
44.2 (43.4, 45.0)
p<0.05 by t-test for comparisons within each variable with indicated reference level
≥1
Reference level
29.7 (26.9, 32.4)13.9 (13.1, 14.8)45.6 (42.5, 48.7)27.3 (26.2, 28.3)51.3 (48.1, 54.4)31.6 (30.5, 32.8)
Smoking status
Current smoker
Reference level
34.4 (30.5, 38.4)15.2 (13.9, 16.5)51.6 (47.8, 55.5)29.5 (28.2, 30.9)58.1 (54.4, 61.7)33.8 (32.3, 35.2)
Former smoker38.2 (35.1, 41.3)20.2 (19.4, 21.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
57.0 (54.0, 60.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
35.8 (34.8, 36.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
62.6 (59.6, 65.6)41.3 (40.2, 42.4)
p<0.05 by t-test for comparisons within each variable with indicated reference level
Never smoked34.2 (32.3, 36.0)20.1 (19.4, 20.8)
p<0.05 by t-test for comparisons within each variable with indicated reference level
53.1 (51.1, 55.2)36.7 (35.9, 37.6)
p<0.05 by t-test for comparisons within each variable with indicated reference level
58.3 (56.3, 60.4)42.3 (41.4, 43.1)
p<0.05 by t-test for comparisons within each variable with indicated reference level
MSA
In MSA34.9 (33.3, 36.4)19.3 (18.8, 19.8)53.6 (51.9, 55.3)35.2 (34.6, 35.9)59.1 (57.5, 60.8)40.4 (39.8, 41.1)
Not in a MSA
Reference level
38.6 (33.7, 43.5)18.8 (17.3, 20.3)55.8 (50.9, 60.7)34.4 (32.8, 35.9)60.2 (55.5, 64.9)39.8 (38.1, 41.5)
Note: This table is based on interviews conducted during March through June 2010 only.
BRFSS, Behavioral Risk Factor Surveillance Survey; MSA, metropolitan statistical area
a Reference level
b p<0.05 by t-test for comparisons within each variable with indicated reference level
State-specific H1N1 vaccination coverage among HCP ranged from 18.4% in Mississippi to 56.1% in Massachusetts with a median of 37.7% among all states. Seasonal influenza vaccination coverage ranged from 40.4% in Florida to 73.1% in Nebraska with a median of 56.8% among all states. Any-dose influenza vaccination coverage ranged from 48.2% in Florida to 77.4% in Nebraska, with a median of 63.8% among all states (Table 3, Figure 1). Using the state-specific figures, the 2009 H1N1, seasonal influenza, and any-dose influenza vaccination coverage among HCP and non-HCP were correlated (r =0.8, 0.5, and 0.6, respectively).
Table 3State-specific H1N1 and seasonal influenza vaccination coverage among healthcare personnel aged ≥18 years, BRFSS 2010, % (95% CI) unless otherwise noted
Sample size, nHealthcare personnel, %H1N1 vaccination coverage
To increase sample size and get reliable state-specific H1N1 vaccination coverage, data were analyzed from interviews conducted November 2009–June 2010 to estimate the cumulative proportion of people vaccinated during October 2009–May 2010 using the Kaplan-Meier survival analysis procedure. To increase sample size and get reliable state-specific seasonal influenza vaccination coverage, data were analyzed from interviews conducted October 2009–June 2010 to estimate the cumulative proportion of people vaccinated August 2009–May 2010 using the Kaplan-Meier survival analysis procedure.
Seasonal influenza vaccination coverage
To increase sample size and get reliable state-specific H1N1 vaccination coverage, data were analyzed from interviews conducted November 2009–June 2010 to estimate the cumulative proportion of people vaccinated during October 2009–May 2010 using the Kaplan-Meier survival analysis procedure. To increase sample size and get reliable state-specific seasonal influenza vaccination coverage, data were analyzed from interviews conducted October 2009–June 2010 to estimate the cumulative proportion of people vaccinated August 2009–May 2010 using the Kaplan-Meier survival analysis procedure.
Any influenza vaccination coverage (seasonal and/or H1N1)
To increase sample size and get reliable state-specific H1N1 vaccination coverage, data were analyzed from interviews conducted November 2009–June 2010 to estimate the cumulative proportion of people vaccinated during October 2009–May 2010 using the Kaplan-Meier survival analysis procedure. To increase sample size and get reliable state-specific seasonal influenza vaccination coverage, data were analyzed from interviews conducted October 2009–June 2010 to estimate the cumulative proportion of people vaccinated August 2009–May 2010 using the Kaplan-Meier survival analysis procedure.
State
Nevada2,9228.329.5 (21.8, 39.0)41.1 (33.1, 50.2)48.4 (39.4, 58.3)
Tennessee3,6808.633.7 (25.9, 43.1)64.6 (56.1, 73.1)70.0 (61.5, 78.2)
Colorado7,2329.840.5 (34.8, 46.7)63.0 (57.2, 68.8)69.0 (63.3, 74.4)
Texas10,75610.328.6 (23.6, 34.4)56.2 (50.3, 62.2)62.4 (56.5, 68.3)
California10,41010.338.9 (32.4, 46.2)53.3 (46.8, 60.1)64.5 (57.1, 72.0)
Wyoming3,78610.843.9 (37.0, 51.5)59.4 (52.7, 66.3)66.4 (59.8, 72.9)
Missouri3,16110.918.5 (9.9, 33.0)53.3 (37.4, 70.9)58.8 (42.7, 75.7)
Oklahoma5,45711.026.8 (22.1, 32.2)56.8 (49.6, 64.3)61.2 (53.7, 68.8)
West Virginia2,96711.134.6 (28.0, 42.1)58.3 (51.2, 65.7)63.2 (55.8, 70.5)
Utah5,82711.147.4 (41.0, 54.2)63.3 (57.4, 69.2)69.2 (63.0, 75.2)
Idaho5,20711.237.7 (32.2, 43.7)55.0 (49.6, 60.5)61.1 (55.4, 66.9)
Georgia3,45111.229.0 (21.2, 39.0)46.5 (39.3, 54.3)55.8 (47.1, 64.9)
District of Columbia2,35611.320.6 (14.5, 29.0)45.8 (35.5, 57.5)49.5 (38.9, 61.4)
Washington12,19511.348.4 (43.4, 53.6)58.9 (54.5, 63.4)68.7 (64.1, 73.1)
Hawaii4,97311.452.4 (43.9, 61.5)56.3 (50.3, 62.5)71.6 (64.4, 78.5)
Louisiana4,51011.729.7 (23.8, 36.6)55.6 (49.4, 61.9)63.4 (56.9, 69.8)
Arizona3,64311.835.0 (26.8, 44.9)50.6 (39.4, 62.9)59.5 (48.1, 71.2)
Montana4,80712.042.3 (36.4, 48.8)55.9 (49.8, 62.3)63.6 (57.5, 69.7)
Mississippi6,08912.118.4 (13.8, 24.2)48.1 (42.8, 53.8)52.9 (47.2, 58.7)
Florida18,41612.125.4 (21.7, 29.6)40.4 (36.1, 45.0)48.2 (43.4, 53.3)
Alabama4,90812.220.4 (15.2, 27.2)47.3 (40.5, 54.7)50.7 (43.1, 58.9)
North Carolina7,48812.239.9 (34.1, 46.1)56.7 (50.9, 62.7)63.6 (57.6, 69.5)
New Mexico4,34312.444.5 (35.2, 55.0)59.5 (51.9, 67.3)67.1 (58.8, 75.3)
Oregon3,70512.541.8 (34.8, 49.7)53.3 (46.6, 60.2)61.5 (54.4, 68.8)
New Jersey7,56312.628.1 (23.7, 33.2)47.3 (42.1, 52.7)53.0 (47.4, 58.9)
New Hampshire3,56612.853.5 (45.6, 61.9)63.1 (56.0, 70.2)72.5 (65.1, 79.5)
Virginia3,26812.934.3 (27.0, 43.0)55.9 (47.3, 64.9)61.2 (51.5, 71.1)
Michigan5,90413.134.5 (29.4, 40.2)52.2 (46.9, 57.7)59.7 (54.1, 65.3)
Ohio6,95213.239.4 (34.6, 44.7)58.7 (54.2, 63.3)65.1 (60.4, 69.8)
Arkansas2,50513.331.8 (23.8, 41.7)65.7 (56.1, 75.0)68.9 (59.4, 77.9)
Kentucky5,25613.333.0 (27.1, 39.7)61.5 (55.7, 67.4)68.6 (62.5, 74.4)
Wisconsin2,01813.449.4 (40.9, 58.7)68.3 (60.2, 76.1)73.4 (65.6, 80.6)
Indiana5,66813.439.5 (33.4, 46.4)53.1 (47.5, 59.0)63.1 (56.7, 69.6)
New York4,74013.430.5 (24.5, 37.6)57.3 (50.8, 63.9)61.3 (54.5, 68.1)
Illinois2,77913.535.9 (27.8, 45.5)54.0 (44.6, 63.9)58.2 (48.8, 67.9)
South Carolina6,29013.529.0 (22.9, 36.4)53.8 (46.7, 61.1)58.8 (50.8, 66.9)
Pennsylvania6,47213.631.9 (27.4, 36.9)60.9 (54.5, 67.3)65.7 (59.5, 71.8)
Maine5,00313.754.1 (46.5, 62.0)68.4 (62.4, 74.3)76.6 (70.3, 82.4)
Rhode Island4,30913.944.4 (38.3, 51.0)60.4 (54.5, 66.3)67.8 (61.9, 73.7)
Kansas7,32913.935.5 (30.9, 40.5)56.4 (51.6, 61.3)63.8 (58.7, 69.0)
Maryland5,90614.240.5 (33.6, 48.3)56.9 (51.4, 62.6)65.0 (57.9, 72.1)
Alaska1,31314.454.1 (39.8, 69.7)62.1 (48.1, 76.2)69.0 (54.7, 82.3)
North Dakota3,24114.642.2 (33.6, 51.9)63.2 (57.0, 69.4)70.3 (62.2, 78.0)
Connecticut3,85114.935.8 (29.0, 43.6)54.4 (47.0, 62.1)58.3 (50.7, 66.1)
South Dakota4,62115.152.3 (46.6, 58.3)68.8 (63.6, 73.8)76.8 (72.0, 81.4)
Massachusetts10,30815.156.1 (51.3, 61.0)66.9 (62.5, 71.4)74.2 (70.1, 78.1)
Nebraska10,24015.448.6 (41.9, 55.7)73.1 (66.5, 79.4)77.4 (71.1, 83.2)
Iowa3,78015.845.9 (39.8, 52.5)70.5 (64.8, 76.0)75.9 (70.0, 81.5)
Minnesota4,56816.044.1 (37.8, 50.9)64.0 (57.7, 70.3)67.7 (61.4, 74.0)
Delaware2,983
Influenza vaccination data were not collected for Delaware and Vermont.
Influenza vaccination data were not collected for Delaware and Vermont.
Influenza vaccination data were not collected for Delaware and Vermont.
Influenza vaccination data were not collected for Delaware and Vermont.
Vermont4,414
Influenza vaccination data were not collected for Delaware and Vermont.
Influenza vaccination data were not collected for Delaware and Vermont.
Influenza vaccination data were not collected for Delaware and Vermont.
Influenza vaccination data were not collected for Delaware and Vermont.
Median12.537.756.863.8
Range8.3–16.018.4–56.140.4–73.148.2–77.4
a To increase sample size and get reliable state-specific H1N1 vaccination coverage, data were analyzed from interviews conducted November 2009–June 2010 to estimate the cumulative proportion of people vaccinated during October 2009–May 2010 using the Kaplan-Meier survival analysis procedure. To increase sample size and get reliable state-specific seasonal influenza vaccination coverage, data were analyzed from interviews conducted October 2009–June 2010 to estimate the cumulative proportion of people vaccinated August 2009–May 2010 using the Kaplan-Meier survival analysis procedure.
b Influenza vaccination data were not collected for Delaware and Vermont.

## Discussion

Healthcare personnel were more likely to be vaccinated with H1N1 and seasonal influenza vaccine than those who were non-HCP; even among HCP, only about one in three received H1N1 vaccination and about one in two received seasonal-only or any-dose vaccination. Overall, H1N1 vaccination coverage among HCP (34.1%) was lower than usual seasonal influenza vaccination coverage among HCP in recent seasons (50%–62%), including the seasonal coverage reported in our analysis,
CDC
Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices.
• Lu P.J.
• Bridges C.B.
• Euler G.L.
• Singleton J.A.
Influenza vaccination of recommended adult populations, U.S., 1989–2005.
• Walker F.J.
• Singleton J.A.
• Lu P.J.
• Wooten K.G.
• Strikas R.A.
Influenza vaccination of healthcare workers in the U.S., 1989–2002.
• Lorick S.A.
• Wortley P.M.
• Lindley M.C.
• Bardenheier B.H.
• Euler G.L.
U.S. Healthcare personnel and influenza vaccination during the 2004–2005 vaccine shortage.
CDC
Interim results: Influenza A (H1N1) 2009 monovalent and seasonal influenza vaccination coverage among health-care personnel—U.S., August 2009–January 2010.
which was well below the Healthy People 2020 objectives of 90%.
Despite HCP being included in the initial target groups recommended by the ACIP to receive the H1N1 vaccination, vaccination coverage was low. Vaccine unavailability at the time of epidemic activity may have contributed to the low H1N1 vaccination coverage.
CDC
Use of influenza A (H1N1) 2009 monovalent vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009.
CDC
Update on influenza A (H1N1) 2009 monovalent vaccines.
CDC
National influenza vaccination week—January 10–16, 2010.
CDC
Update: influenza activity—U.S., August 30, 2009–March 27, 2010, and composition of the 2010–11 influenza vaccine.
CDC
Update: influenza activity—U.S., August 30, 2009–January 9, 2010.
CDC
Interim results: influenza A (H1N1) 2009 monovalent vaccination coverage—U.S., October–December 2009.
One study
• Harris K.
• Maurer J.
• Black C.
• Euler G.
Workplace efforts to promote influenza vaccination among healthcare personnel and their association with uptake during the 2009 pandemic influenza A (H1N1).
showed that 17.3% of unvaccinated HCP listed unavailability of 2009 H1N1 vaccine as a reason for nonvaccination.
CDC
Interim results: Influenza A (H1N1) 2009 monovalent and seasonal influenza vaccination coverage among health-care personnel—U.S., August 2009–January 2010.
In addition, not all healthcare settings offered worksite influenza vaccination. Worksite vaccination could significantly increase seasonal and H1N1 vaccination coverage among HCP, but one study
• Harris K.
• Maurer J.
• Black C.
• Euler G.
Workplace efforts to promote influenza vaccination among healthcare personnel and their association with uptake during the 2009 pandemic influenza A (H1N1).
showed that one third of healthcare settings did not offer on-site vaccination for HCP.
Vaccination coverage among HCP for H1N1 and seasonal influenza varied widely by state. Variation by state in vaccination coverage among the general adult population also has been observed.
CDC
Interim results: state-specific seasonal influenza vaccination coverage—U.S., August 2009–January 2010.
Factors that may have contributed to the wide variation in vaccination coverage include the following: epidemic activity had virtually declined or disappeared in many southern states when vaccine became available, whereas it was still ongoing in many northern states
CDC
National influenza vaccination week—January 10–16, 2010.
CDC
Update: influenza activity—U.S., August 30, 2009–March 27, 2010, and composition of the 2010–11 influenza vaccine.
CDC
Update: influenza activity—U.S., August 30, 2009–January 9, 2010.
; wide variations in state-specific vaccination program and pandemic planning preparation: states that were well prepared for a pandemic may have found it easier to implement vaccination programs on very short notice
• Klaiman T.
• Ibrahim J.K.
State health department structure and pandemic planning.
; and differences in the effectiveness of specific intervention programs being implemented by states (i.e., community campaigns, provider-based strategies, and workplace vaccination).
• Klaiman T.
• Ibrahim J.K.
State health department structure and pandemic planning.

Nelson DE, Bland S, Powell-Griner E, et al. State trends in health risk factors and receipt of clinical preventive services among U.S. adults during the 1990s. JAMA;287(20):2659–67.

Influenza vaccination among HCP legislation also may influence vaccination coverage. During the time of the pandemic, eight states had influenza vaccination legislation requirements among HCP, either to offer (seven states) or ensure vaccination (one state). Of those eight states, six had influenza vaccination coverage among HCP that was higher than the national average, which may indicate that legislation requirements help increase vaccination coverage. Vaccination coverage among HCP may be further increased when more states recommend or require influenza vaccination for HCP.
In the current study, vaccination coverage was found to be higher among HCP who have a regular physician and have visited a physician for a routine checkup within 1 year than among those who did not. Physician contacts play an important role in vaccination uptake.
• Walker F.J.
• Singleton J.A.
• Lu P.J.
• Wooten K.G.
• Strikas R.A.
Influenza vaccination of healthcare workers in the U.S., 1989–2002.
• Lorick S.A.
• Wortley P.M.
• Lindley M.C.
• Bardenheier B.H.
• Euler G.L.
U.S. Healthcare personnel and influenza vaccination during the 2004–2005 vaccine shortage.
HCP may have more-frequent contacts than do non-HCPs with their healthcare providers. Routine physician visits can provide important opportunities for providers to vaccinate HCP. The current study found that race/ethnicity, income, high-risk conditions status, and health insurance status were also independently associated with vaccination. Those findings concurred with those of previous studies.
• Walker F.J.
• Singleton J.A.
• Lu P.J.
• Wooten K.G.
• Strikas R.A.
Influenza vaccination of healthcare workers in the U.S., 1989–2002.
• Lorick S.A.
• Wortley P.M.
• Lindley M.C.
• Bardenheier B.H.
• Euler G.L.
U.S. Healthcare personnel and influenza vaccination during the 2004–2005 vaccine shortage.
Studies showed that 2009 H1N1 vaccination coverage among HCP in other countries was 18% in Italy and 22% in Spain. Coverage among HCP was 92% in South Korea and 79% in Thailand.
• Sánchez-Payá J.
• Hernández-García I.
• Barrenengoa Sañudo J.
• et al.
Determinants of influenza vaccination in health staff: 2009-2010 season.
• Amodio E.
• Anastasi G.
• Marsala M.G.
• Torregrossa M.V.
• Romano N.
• Firenze A.
Vaccination against the 2009 pandemic influenza A (H1N1) among healthcare workers in the major teaching hospital of Sicily (Italy).
• Park S.W.
• Lee J.H.
• Kim E.S.
• et al.
Adverse events associated with the 2009 H1N1 influenza vaccination and the vaccination coverage rate in health care workers.
• Kiertiburanakul S.
• Malathum K.
• Watcharananan S.P.
• et al.
High coverage and safety of influenza A (H1N1) 2009 monovalent vaccination among health care personnel in Thailand.
There are likely factors that contribute to higher coverage. A well-prepared vaccination plan with strong support from hospital administrators, free vaccine, and well-distributed H1N1 pandemic information may have contributed to the higher vaccination coverage among HCP in South Korea and Thailand.
• Park S.W.
• Lee J.H.
• Kim E.S.
• et al.
Adverse events associated with the 2009 H1N1 influenza vaccination and the vaccination coverage rate in health care workers.
• Kiertiburanakul S.
• Malathum K.
• Watcharananan S.P.
• et al.
High coverage and safety of influenza A (H1N1) 2009 monovalent vaccination among health care personnel in Thailand.
In addition, Thailand was a SARS (severe acute respiratory syndrome) epicenter and has been dealing with H5N1 (avian influenza) outbreaks.
• Lee N.E.
• Siriarayapon P.
• Tappero J.
• et al.
Infection control practices for SARS in Lao People's Democratic Republic, Taiwan, and Thailand: experience from mobile SARS containment teams, 2003.
• Chantong W.
• Kaneene J.B.
Poultry raising systems and highly pathogenic avian influenza outbreaks in Thailand: the situation, associations, and impacts.
• Keawcharoen J.
• van den Broek J.
• Bouma A.
• Tiensin T.
• Osterhaus A.D.
• Heesterbeek H.
Wild birds and increased transmission of highly pathogenic avian influenza (H5N1) among poultry, Thailand.
This past experience probably increased support for pandemic planning and implementation.
The findings in this paper are subject to several limitations. First, BRFSS is a landline, telephone-based survey that excludes people without telephones and those with only cellular phones and thus may produce a biased coverage estimate
• Blumberg S.J.
• Luke J.V.
Reevaluating the need for concern regarding non-coverage bias in landline surveys.
; however, weight was adjusted to account for people without landline telephones and people with cell phone only.
CDC
2009 BRFSS Summary Data Quality Report.
• Blumberg S.J.
• Luke J.V.
Reevaluating the need for concern regarding non-coverage bias in landline surveys.
Second, vaccination status is self-reported and is subject to recall bias. However, self-reported influenza vaccination status has been shown to have relatively high agreement with medical records among older adults.
• Donald R.M.
• Baken L.
• Nelson A.
• Nichol K.L.
Validation of self-report of influenza and pneumococcal vaccination status in elderly outpatients.
• Zimmerman R.K.
• Raymund M.
• Janosky J.E.
• Nowalk M.P.
• Fine M.J.
Sensitivity and specificity of patient self-report of influenza and pneumococcal polysaccharide vaccinations among elderly outpatients in diverse patient care strata.
• Mangtani P.
• Shah A.
• Roberts J.A.
Validation of influenza and pneumococcal vaccine status in adults based on self-report.
Comprehensive strategies are needed to further improve uptake of vaccination coverage for HCP. Recommended approaches include emphasizing the benefits of HCP vaccination for staff and patients; considering the level of vaccination coverage among HCP to be one measure of patient safety and quality assurance; electronic tracking of coverage levels by ward, unit, and occupation; providing vaccinations in the workplace so they are easily accessible; and implementing catch-up vaccination programs for HCP who are already employed and ensuring that newly hired HCP receive necessary vaccinations.
CDC
Immunization of health-care workers: recommendations of the Advisory Committee on Immunization Practices (ACIP) and the Hospital Infection Control Practices Advisory Committee (HICPAC).
CDC
Influenza vaccination of health-care personnel.
• Poland G.A.
• Shefer A.M.
• McCauley M.
• et al.
• Lindley M.C.
• Horlick G.A.
• Shefer A.M.
• Shaw F.E.
• Gorji M.
Assessing state immunization requirements for healthcare workers and patients.
Guide to Community Preventive Services.
The authors thank Elizabeth Monsell, James A. Singleton, Gary L. Euler, Stacy M. Greby, and Abigail M. Shefer for their important contributions to this manuscript.
The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of CDC.
No financial disclosures were reported by the authors of this paper.

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