- The meningococcal conjugate vaccine (MCV4) was recommended for those aged 11–18 years in 2005. Initial supply issues led to an emphasis on immunizing older adolescents. When supply improved in 2007, routine immunization was recommended for those aged 11–12 years.
- The effects of delayed influenza vaccine delivery on primary practices are currently unknown.
- Little is known about the effects of increased parental vaccine safety concerns on physicians' vaccine communication attitudes and practices.