New research shows that vaccinating children against rotavirus may prevent more than intestinal illness. Immunization significantly reduced the risk of severe rotavirus-related seizures that required hospitalization or emergency department care.
Researchers from the Centers for Disease Control and Prevention and several other institutions analyzed records of some 250 000 US children born between March 2006 and November 2009. About three-fourths were fully immunized against rotavirus. All were enrolled in the Vaccine Safety Datalink, a national initiative that collects information for vaccine safety research.
Overall, 2244 of the children had at least 1 seizure. The researchers calculated that children who were fully vaccinated against rotavirus had a first seizure at a rate of 1145 per 100 000 person-years compared with 1212 per 100 000 person-years among children who hadn’t received any doses of rotavirus vaccine. For all seizures, the rate among vaccinated children was 1383 per 100 000 person-years and 1502 per 100 000 person-years among unvaccinated children.
Further analysis showed that compared with unvaccinated children, those who were fully vaccinated had a statistically significant 20% reduced risk of having a seizure that required emergency department care or hospitalization.
The study authors noted that the degree of risk reduction they found could help prevent about 1000 hospitalizations and 5000 emergency department visits annually for seizures among young children. The cost savings from preventing rotavirus-related seizures could reach $7 million or more per year, they added. Their findings were published today in the journal Clinical Infectious Diseases.
Rotavirus infection causes gastroenteritis but also may result in complications involving the central nervous system. Previous research in Canada estimated that about 7% of children infected with rotavirus have a seizure. A study in a single US hospital showed that 18% of children with a rotavirus-related seizure spent at least 1 day in an intensive care unit and 59% had a lumbar puncture.
A pentavalent rotavirus vaccine became available in 2006 and a monovalent formulation was introduced in 2008. In an accompanying editorial, Geoffrey Weinberg, MD, of the University of Rochester School of Medicine in New York, noted that the vaccines have been “extraordinarily successful.” A study published earlier this year showed that positive results from laboratory testing for rotavirus infection have decreased by at least 74% since the vaccines became available.
“Work such as this not only is interesting scientifically, but provides yet another reason to strongly promote universal rotavirus immunization,” Weinberg wrote. “Sometimes, unexpected effects of vaccination… are a cause for celebration rather than the more commonly publicized concern for unexpected adverse effects.”