Washington – The government warned Tuesday of potentially life-threatening twisting of the intestines in infants vaccinated against a virus that is the leading cause of early childhood diarrhea.
The condition, called intussusception, is the same that led to the withdrawal of the first rotavirus vaccine eight years ago.
The Food and Drug Administration said it was unknown whether the recently approved RotaTeq vaccine caused the 28 new cases. The condition also can occur spontaneously.
Indeed, the reports don’t exceed the numbers expected to occur naturally each year – the so-called background rate.
“It looks like this is the natural background rate that we are seeing,” said Dr. Michelle Goveia, medical director for pediatric medical affairs at the vaccine’s manufacturer, Merck & Co. Goveia suggested heightened concerns about the previous vaccine, made by Wyeth, prompted the FDA to act.
In Tuesday’s public-health notification, the FDA said it wanted, in part, to encourage reporting of any additional cases of intestinal twisting or blockage to help it assess any risks associated with the three-shot series. It also said the label would mention cases of intussusception.
The vaccine’s co-inventor, Dr. Paul Offit of the Children’s Hospital of Philadelphia, said the 28 reports were well below the hundreds of cases one would expect naturally. He suggested the FDA wanted to “shake the tree” for more reports about the vaccine.
The 28 cases included 16 infants who required intestinal surgery. There have been no reports of deaths.
RotaTeq got FDA approval in February 2006. At the time, the FDA and Merck said vaccine trials involving nearly 70,000 infants indicated it did not raise the risk of intussusception.
In the U.S., rotavirus sickens about 2.7 million children younger than 5, sends up to 70,000 to the hospital and causes 20 to 70 deaths each year.
