Rotavirus Vaccine Has Cut Hospitalization of Kids

Sept. 21, 2011 -- Far fewer children were hospitalized for a common stomach bug known as rotavirus since routine vaccination was recommended in 2006, a study shows.

The new findings appear in the New England Journal of Medicine.

The CDC recommends that infants get vaccinated for rotavirus. There are two available rotavirus vaccines. The RotaTeq vaccine is given in three doses at ages 2 months, 4 months, and 6 months. The Rotarix vaccine is given as two doses at 2 months and 4 months.

What Is Rotavirus?

Rotavirus is a common cause of diarrheal illness, especially in children. Symptoms include fever, abdominal pain, vomiting, and diarrhea. It ranges from the mild to the severe. Rotavirus is spread easily from child to child via hand-to-mouth contact. Rotavirus is most likely seen during winter and spring in the U.S.

Before the CDC recommended routine rotavirus vaccination, rotavirus caused in the U.S. each year:

• 400,000 visits to doctors' offices by children under age 5 for rotavirus infection
• 200,000 emergency room visits 
• 55,000 to 70,000 hospitalizations

"This is a staggering figure," says study researcher Umesh Parashar, MBBS, MPH. He is a medical epidemiologist and team leader for the viral gastroenteritis team of the CDC's division of viral diseases. "It means that one in 70 children born in the United States during the pre-vaccine era was hospitalized for rotavirus by age 5."

After the CDC got behind vaccination in 2006, there was a substantial drop in the number of severe rotavirus illnesses and associated health care costs. This drop was seen during the rotavirus seasons of 2007-2008 and 2008-2009.

Fewer kids were hospitalized due to rotavirus as well; many of them may have benefited from other children getting the vaccine even if they didn't. There were 60% to 75% fewer hospital admissions among kids due to rotavirus after the vaccine became available, the study showed. This drop was even more pronounced among children who got the vaccine.

As a result, there was also a sharp a reduction in the costs of treating the illness.

Rotavirus Vaccine Risks

The main concern with the rotavirus vaccine is a risk of intussusception, a potentially life-threatening bowel blockage. An earlier rotavirus vaccine was removed from the market because it increased risk for intussusception.

As far as the newer rotavirus vaccines, "there have been data from international settings including Mexico, Brazil, and Latin America that suggest a low level risk of intussusception," Parashar says. In general, "this risk is five- to 10-fold lower than what was seen with the earlier rotavirus vaccine."

This level of risk has not been seen in the U.S., he says.

But "we still don't have enough to confidently exclude a low risk," Parashar says. According to the CDC, the estimated risk of intussusception is one case per 100,000 infants.