According to an investigation by child health experts at C.S. Mott Children’s Hospital, the updated rotavirus vaccines do not seem to increase the occurrence of gastrointestinal complications, even though it was taken off the market in 1999 after being linked to these potentially deadly adverse effects. The study is published this week in Archives of Pediatric Adolescent Medicine.

In 2006 and 2008 the two updated versions of the vaccine were re-introduced. Symptoms of rotavirus include:

  • Abdominal pain
  • Nausea
  • Severe diarrhea
  • Vomiting
  • Poor feeding
  • Chills
  • Weight loss
  • Muscle pain

Young infants and children infected with rotavirus frequently require hospitalization. In the U.S., rotavirus was once the primary cause of gastrointestinal illness among infants and children.

The study demonstrates that the updated vaccine has not resulted in an increase in intussusception (severe bowel obstruction), the adverse effect that caused the first vaccine to be withdrawn.

Joe Zickafoose. M.D., M.S., lead author of the study, pediatrician and research fellow with the Child Health Evaluation and Research Unit explained:

“We always need to carefully weigh the risks and benefits of childhood vaccines. Fortunately, our results suggest that rotavirus vaccines have not increased the rate of intussusception in the U.S.”

Although, international investigations demonstrated that the updated vaccines might be linked to a small increase in intussusception cases in infants, hospitalization rates for intussusception in the U.S., did not seem to increase.

In the United States, over 70% of infants have received the vaccination. The updated vaccines are credited with lowering the incidence of diarrhea-related hospitalizations, outpatient visits and emergency department visits among children.

The team used data from the Healthcare Cost and Utilization Project’s Kids’ Inpatient Database, which is a sample of 80% of national pediatric discharges. Based on previous data which indicated that the majority of intussusception cases occur within weeks of the vaccine being administered at ages 2, 4 and 6 months, the researchers focused on children younger than 1 year of age.

The researchers analyzed data trends from 1997 to 2006 (the decade prior to vaccine re-introduction) and compared them with data trends after the updated vaccines were re-introduced.

Although they anticipated to see 36 intussusception-related hospitalizations per 100,000 children under the age of 1 by 2009, they found only 33.3 hospitalizations per 100,000 children, indicating that the vaccine was highly unlikely to cause additional cases.

The updated vaccines were licensed after investigations in more than 70,000 children revealed no increased risk for intussusception among children who received the vaccination. Although, there have been concerns that these studies may have missed a small amount of risk.

Zickafoose said:

“We hope that our study provides information that will continue to reassure parents that the benefits of rotavirus vaccine outweigh the risks.”

Written by Grace Rattue