On February 13, 2007, the U.S. Food and Drug Administration (FDA) notified the public of 28 cases of infant intussusception linked to RotaTeq, a vaccine given for the prevention of Rotavirus infection. The most common abdominal emergency in children under two years old, intussusception occurs when one portion of the bowel slides into the next, much like a zoom photo lens does when it retracts. Intussusception creates an obstruction in the bowel, with the walls of the intestines pressing against one another.

Rotaviruses are the most common cause of dehydration and diarrhea in infants and young children, causing 20 deaths per year in the U.S.

Of the 28 reported cases of intussusception, the number caused by the RotaTeq vaccine is not actually known because the disorder may have occurred in this population. Further indication that natural incidence is a possibility lies in the finding that reported cases of intussusception in RotaTeq-vaccinated children occurred after the first, second and third vaccinations in the three dosage series, exhibiting no specific pattern of disorder.

This was not the case for an earlier vaccine against the Rotavirus, RotaShield, where the incidence of onset of intussusception developed a more obvious pattern. RotaSheild, manufactured by Wyeth, was suspended from sale in July 1999, only one year after approved by the FDA after 15 reports of intussusception of the bowel had been made to federal regulators. At that time 1.5 million doses of RotaShield had been given.

According to the FDA 3.5 million doses of RotaTeq vaccine have been distributed in the US through February 1, 2007, but not all these doses have been dispensed.

The 28 RotaTeq-vaccinated infants in the reported cases did not have an easy treatment course. The intussusception of 12 of the infants was treated by reduction of the blockage by enema. The remaining 16 infants required surgery.

The FDA stated that more cases of intussusception with RotaTeq may have not been reported. The FDA is urging parents to contact their vaccinated child’s doctor immediately if their child has any symptoms of intussusception. Additionally, the FDA asks that all cases of intussusception of the bowel be reported online to the Vaccine Adverse Event Reporting System (VAERS) or by calling 1-800-822-7967.

Common symptoms of intussusception include:

• abdominal swelling or distension,
• passing “currant jelly” stools (bowel movements mixed with blood and mucus),
• vomiting,
• vomiting bile, a gold-brown fluid that the liver secretes which has a bitter taste,
• lethargy (seeming unenergetic, listless, sluggish, or drowsy)
• shallow breathing, and
• the child may sometimes make grunting noises.

Merck & Co., manufacturer of RotaTeq, has updated RotaTeq’s label to inform consumers of the reported cases of intussusception.

Sources: Anna Wilde Mathews and John Carreyroum, “Vaccine Draws FDA Warning,” Wall Street Journal, February 14, 2007; Amanda Hitti, “Serious Bowel Problems Reported in 28 U.S. Babies After Getting RotaTeq Vaccine,” WebMD, February 13, 2007; Bill Berkrot, “Bowel Problem Seen in Infants Given Merck vaccine, ” Scientific American.com, February, 13, 2007; FDA Public Health Notification, ” Information on RotaTeq and Intussusception, “February 13, 2007.