Warning On Infant Vaccine
Health officials are telling parents and doctors to postpone giving children the rotavirus vaccine because it may be associated with a serious side effect - a type of bowel obstruction. CBS News Health Correspondent Dr. Emily Senay reports.
The rotavirus vaccine, administered orally, was just approved in the past year to prevent childhood diarrhea.
The U.S. Centers for Disease Control and Prevention (CDC) said health care providers and parents should delay use of the oral rotavirus vaccine until November, because at least 15 infants who received the vaccine developed intussusception, an obstruction where the bowel folds in on itself.
"We're recommending that vaccination of children who were scheduled to receive the vaccine before November 1999 be postponed," said Dr. Melinda Wharton, chief of the Child Vaccine Preventable Diseases Branch of the CDC's National Immunization Program.
The American Academy of Pediatrics, in response to the CDC report, issued a statement calling for a temporary suspension on the use of the rotavirus vaccine.
Wharton said 15 cases of intussusception had been confirmed among children who received rotavirus vaccines, and additional cases had been identified in two ongoing studies, raising "serious concern."
Symptoms of intussusception include:
- Persistent vomiting
- Red or black-colored stool
- Severe colic-type pain
- Abdominal bloating
Researchers said they needed more time to determine whether the bowel problems were caused by the vaccine manufactured by Wyeth-Ayerst Laboratories, a division of American Home Products Corp. and marketed under the trade name RotaShield.
"Rotavirus is a serious disease and the vaccine has been demonstrated to be very effective," Wharton said. "It's really important to collect more information so that we better understand this problem and its magnitude."
The CDC estimated that 1.5 million doses of the rotavirus vaccine had been administered to infants since it was licensed by the U.S. Food and Drug Administration on Aug. 31, 1998. The live rotavirus vaccine was recommended for healthy infants at two, four and six months of age.
The CDC said parents or caregivers of children who had already received the vaccine should notify their health care providers if an infant develops symptoms of intussusception.
Researchers said the risk of intussusception seemed to be the highest in the first two to three weeks after vaccination.
Rotavirus infections are the most common cause of severe diarrhea and vomiting in infants. The infection peaks during the winter in the United States. About 80 percent of children develop symptoms of rotavirus infection before they are 5 years old.
About 55,000 infants and children were hospitalized and 20 to 40 died each year because of severe diarrhea and dehydration caused by rotaviral disease, health officials said.
Before it was approved by the FDA, the vaccie was studied in almost 7,000 infants in the United States and Europe. In placebo-controlled trials involving about 2,000 infants, the FDA said the vaccine prevented at least half of all cases of rotavirus disease and more than 70 percent of severe cases.
In those studies, intussusception occurred among five of 10,000 vaccine recipients, but the number was not significantly higher than among infants who received placebos, the CDC said.