Twisted Bowels


Ok. That’s a pretty unpleasant title for this rant, but then I awoke to an e-mail from one of the news aggregators I use proclaiming “FDA issues warning on rotavirus vaccine”.

I quickly turned to this story worried that the VAERS (Vaccine Adverse Event Reporting System) had picked up a cluster of intussception on the new oral pentavalent rotavirus vaccine. Here’s how the AP reported it:

FDA: Rotavirus Vaccine May Harm Infants

Published: February 14, 2007
Filed at 12:40 a.m. ET

WASHINGTON (AP) — The government warned on 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 vaccine, called RotaTeq, 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, the FDA said.

”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. Inc. Goveia suggested heightened concerns about the previous vaccine, made by Wyeth, prompted the FDA to act.

In Tuesday’s public health notification, the agency 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 vaccine series. It also said the vaccine’s label would mention the cases of intussusception.

‘It’s a known serious, life-threatening adverse event that is being seen at an expected level postmarketing. But because it is so serious, we asked the company to change the label,” FDA spokeswoman Karen Riley said.

Dr. Paul Offit, the vaccine’s co-inventor, 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.

”I am actually encouraged by those data: 28 cases, when you would have expected at least 500 cases, that is really reassuring,” said Offit, of the Children’s Hospital of Philadelphia. ”I don’t see how those numbers suggest something’s awry. If anything, they suggest nothing’s awry.”

The 28 cases included 16 infants who required intestinal surgery. There have been no reports of deaths.

RotaTeq received FDA approval in February 2006. At the time, the FDA and Merck said trials of the vaccine involving nearly 70,000 infants indicated it did not increase the risk of intussusception. But Merck and the Centers for Disease Control and Prevention are conducting follow-up studies of tens of thousands more infants to track any long-term effects of the vaccine. The FDA also is monitoring reports.

About 3.5 million doses of the Merck vaccine have been distributed in the U.S., though not all have been used, the FDA said.

The earlier rotavirus vaccine, Wyeth’s RotaShield, was pulled from the U.S. market in 1999 after it was linked to a small increase in intussusception. It had been on the market a year.

In the United States, 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.

Now, for anyone who knows a lick of pediatrics, it’s possible to find four major flaws with this story, flaws that reveal what are clearly the machinations of a bored and not-so-bright Associated Press flunkie who had nothing better to do than to twist an FDA release into a story designed to scare parents and physicians.

  • First, intussception is not a “twisting of the intestines”. It is a telescoping of the small bowel. Malrotations and intestinal volvulus (twisting of the intestions) are most definitely not associated with rotavirus vaccine.
  • Second, the current rotavirus vaccine is a three-dose, orally administered vaccine. Not a series of injections. It is hard to trust reporting on a vaccine when the author didn’t care enough to fact check correctly on something as simple as the difference between a vaccine given by injection and by mouth.
  • Third, the story buries in the second paragraph the fact that intussception is a naturally occuring phenomena and that the background rate in children is 1-4 cases per 1000 live births.
  • Finally, the story entirely mischaracterizes the FDA report (which you can read here and interpret for yourselves). The report clearly states, “FDA is issuing this notification both to encourage the reporting of any additional cases of intussusception that may have occurred or occur in the future after administration of RotaTeq (the vaccine brand name), and to remind people that intussusception is a potential complication of RotaTeq.”

I could go on and on about the clinical trial that preceeded the rotavirus vaccine, and also go on and on about the previous rotavirus vaccine and it’s safety issues (and perhaps later I’ll touch up this entry with a link to a fascinating NEJM article on the topic). But my point for this morning is that rather than take the time to accurately report facts, some healthcare journalists (or in this case, wire services) slap stories together with headlines designed to scare patients and families rather than inform them. I can’t wait to see what my friend Flea does with this one.