A vaccine against rotavirus, Rotateq, which causes diarrhea and vomiting in thousands of children every year, has reduced the number of illnesses by at least two-thirds in its second year of use. The vaccine was approved in 2006 and it had a good secondary effect: it has severely slowed down the virus’ spread to non-immunized children in the U.S. The report that mentions these facts was released by the United States Centers for Diseases Control and Prevention and Quest Diagnostics.

Children have to get the three-shot series of Rotateq immunization at 2, 4 and 6 months of age. About 55,000 kids are hospitalized in the U.S. annually because of illness and dehydration caused by the rotavirus. Furthermore, the disease kills more than 600,000 children worldwide each year. Rotateq generated an income of $525 million last year. As for the effect of slowing the spread of the virus, this is known as herd immunity, which is a community’s resistance to illness.

These results have been presented at the Interscience Conference on Antimicrobial Agents and Chemotherapy conference in Washington. 132,000 rotavirus cases were recorded from 2003 to July 2008. Since the Rotateq was cleared for sale, the cases fell more than 76 percent. In some states, such as Delaware, North Carolina and Alabama, they fell more than 95 percent, but in Washington, Nebraska, New Mexico and Arizona they fell only 35 percent.

The data was sent by 33 sentinel laboratories that are part of a voluntary reporting system across the U.S.

Rotateq is an oral vaccine. In June, a second rotavirus vaccine came on the market - GlaxoSmithKline's Rotarix. It requires only two doses, completed by four months of age. Also at the conference, scientists reported that a new version of Wyeth’s Prevnar vaccine seems to better protect children against some germs that cause pneumonia, meningitis and ear infections.