U.S. Varicella Cases Drop Sharply Due to Vaccine
Recommendation for second dose reduced number of infections even more, CDC finds
FRIDAY, Aug. 14, 2015 (HealthDay News) -- Varicella cases in the United States have dropped sharply since a vaccine against the disease became available in 1995, according to a study published online Aug. 12 in the Journal of the Pediatric Infectious Diseases Society.
Before 1995, about four million people in the United States got varicella each year, nearly 11,000 were hospitalized, and up to 150 died of the disease, according to the U.S. Centers for Disease Control and Prevention. For this study, CDC researchers analyzed national health insurance claims data. They found that there were 93 percent fewer hospitalizations for varicella in 2012, and 84 percent fewer outpatient visits for the disease than in the period before the vaccine was introduced. After the second dose recommendation took effect in 2006, hospitalizations dropped 38 percent and outpatient visits declined 60 percent.
The largest decrease in varicella occurred among children and teens aged 1 to 19, a group targeted for vaccination against the disease. But there were also significant drops in outpatient visits and hospitalizations among children younger than 12 months -- for whom the vaccine is not recommended -- and among adults, who tend not to get vaccinated.
"We found that, in our study, rates for varicella in the United States continued to decline as the varicella vaccine program has become fully implemented," study coauthor Jessica Leung, M.P.H., said in a journal news release. "We saw significant declines in rates of varicella after the one-dose vaccine was recommended in 1995 in the United States, and we're continuing to see additional declines in varicella after two doses were recommended in 2006."