WASHINGTON — A vaccine against rotavirus, the leading cause of diarrhea in infants, has led to a dramatic drop in hospitalization and emergency room visits since it came on the market two years ago, doctors reported Saturday.
A bonus: The vaccine seems to be preventing illness even in unvaccinated children by cutting the number of infections in the community that kids can pick up and spread.
"We're a little surprised by the degree of impact given the coverage we've achieved," said Jane Seward of the federal Centers for Disease Control and Prevention. Only about half of young children had received the vaccine and very few had received all three doses when the studies were done.
Results were reported Saturday at an infectious diseases conference in Washington.
Before the vaccine, more than 200,000 U.S. children were taken to emergency rooms and more than 55,000 were hospitalized each year with rotavirus, which causes vomiting and diarrhea, mostly from January through May. Worldwide, the virus kills 1,600 children a day.
Since Merck & Co.'s Rotateq came out in 2006, hospital visits and stays due to the virus have dropped 80 percent to 100 percent, studies by the CDC and several other groups show.
Last winter, rotavirus cases started and peaked two to three months later and were much less extensive than in previous years, CDC scientists report. Hospitals in a network that tracks these cases for the CDC saw more than an 80 percent drop in admissions from them, one study showed.
Rotateq is an oral vaccine given at 2, 4 and 6 months of age. In June, a second rotavirus vaccine came on the market — GlaxoSmithKline's Rotarix. It requires only two doses, completed by 4 months of age.