In a study of more than 68,000 infants published in the New England Journal of Medicine, the investigational vaccine Rotateq demonstrated that it can safely prevent 98 percent of severe cases of viral diarrhea and vomiting that account for 2 million hospital visits and 500,000 pediatric deaths each year worldwide.
In one of the largest pre-licensure vaccine clinical trials ever conducted worldwide, research championed by an Eastern Virginia Medical School investigator demonstrated that the oral vaccine Rotateq virtually eliminated the most severe cases of rotavirus, a common childhood virus that sometimes becomes deadly.
"This is good news for children everywhere," said principal investigator David O. Matson, M.D., professor of pediatrics at Eastern Virginia Medical School (EVMS) and head of infectious diseases at EVMS' Center for Pediatric Research. "In a matter of hours, vomiting and diarrhea from rotavirus can lead to dehydration, which can result in hospitalization and even be life-threatening."
Rotavirus causes about 70,000 hospital admissions in the United States annually, or about five percent of all pediatric admissions. It also results in 250,000 visits each year to U.S. emergency rooms.
In the developing world, where prompt hospitalization and effective treatment may not be available, rotavirus kills half a million infants a year, about one child each minute. Matson, widely regarded as one of the nation's leading rotavirus researchers, has studied the virus for over two decades.
"Development of a safe and effective rotavirus vaccine has been a worldwide priority since the virus was discovered in the 1970s," Matson said. "It became clear at that time that it was one of the major killers of children, and there was no effective treatment."
Rotavirus is endemic and infections occur in almost all children. The severity of rotavirus infection ranges from no symptoms to dehydrating gastroenteritis that can be fatal.
Efforts to eradicate rotavirus disease were almost derailed in 1999 when another vaccine was pulled from the market because it caused a rare bowel obstruction called intussusception at a rate of one in 10,000 patients. Intussusception takes place when the bowel folds in on itself, causing an intestinal blockage.
Because the bowel obstruction was so rare, and the increased incidence was so small, the only way to evaluate the safety of a new rotavirus vaccine was to launch a clinical trial involving more than 60,000 infants.
In 2000, Merck asked Matson to serve as the U.S. principal investigator in a clinical trial of RotaTeq, a vaccine under development.
RotaTeq targets five major strains of rotavirus, which account for 90 percent of rotavirus disease. The trial involved infants in the United States, Belgium, Costa Rica, Finland, Germany, Guatemala, Italy, Jamaica, Mexico, Sweden and Taiwan.