New Guidelines for Chicken Pox Vaccination
July 5, 2007
New Guidelines for Chicken Pox Vaccination
It was the last of the common childhood diseases to be prevented by vaccination, and since a varicella vaccine was introduced in 1995, there has been a marked reduction from the estimated 4 million cases of chicken pox that occurred annually in the United States. Initially recommended by the Advisory Committee on Immunization Practices (ACIP) for administration to healthy children aged up to 12 months, and to previously unvaccinated adolescents and adults, the vaccine seemed to be highly effective, but increasing reports of outbreaks of chicken pox among highly vaccinated populations have caused the ACIP to upgrade its recommendations. The most recent suggestions, published June 22 in the CDC publication Morbidity and Mortality Weekly Report (MMWR), note that in the 10-year observation period, comparisons of one-dose and two-dose regimens showed onset of chicken pox after vaccination was more likely when children and adolescents were given just one dose of the vaccine. That is leading the ACIP to recommend that infants and young children be given two doses, one at 12 to 15 months of age and another at 4 to 6 years. For adults and adolescents, two doses 4 to 8 weeks apart are now recommended for all adolescents and adults that have no evidence of immunity, with a catch-up of two doses for persons who received the previously recommended one catch-up dose. Varicella vaccination is now recommended for children attending child care centers, students in all grade levels, and persons attending college or other postsecondary education institutions. The report, "Prevention of Varicella," dated June 22, 2007, is available online at www.cdc.gov/mmwr.