Rotavirus infections -- viruses that cause diarrhea -- kill about 750,000 children worldwide each year. In the United States alone more than 50,000 children are hospitalized each year, and of that number nearly 50 cases will be fatal. A vaccine, then, against this viral killer has long been sought by biomedical researchers throughout the world.
The scientific breakthrough for rotavirus came about a decade ago, and approximately five years after that the National Institutes of Allergy and Infectious Diseases (NIAID), the lead institute of the National Institutes of Health (NIH) for vaccine development, gave its blessing to move forward with a vaccine. The vaccine passed muster in small-, then intermediate-, sized clinical trials, and last year was released for mass vaccination. A month ago, the vaccine --called RotaShield -- was withdrawn from the market.
Rotavirus spreads through the fecal-oral transmission, like polio, hepatitis A, and many other viral diseases. While not in itself a fatal disease -- like cholera -- if untreated, it results in severe dehydration, and without prompt medical treatment (which primarily involves replacement of fluid), can be fatal. It is obviously a very serious problem in Third World countries where access to modern medical care is limited.
Once the diarrhea vaccine was available, the issues that the authorities had to wrestle with involved, as always, risk vs. reward. The issue is straightforward: every month that the vaccine was held back, children were dying throughout the world. The first trial involved about 300 children. No serious complications were reported, although, in retrospect, one of the doctors involved in the trial (held in China) thinks there may have been some mild cases of intestinal obstruction. None of the children vaccinated needed hospitalization.
The next, larger trial involved nearly 10,000 children, and five cases of bowel obstruction were seen. (There was one case in the 5,000 unvaccinated controls, a difference that is not statistically significant.) Authorities had to deal with the situation on these levels: The vaccine was desperately needed, and children get bowel obstruction at about this rate even if they are not vaccinated -- indeed, the rate of hospitalization for bowel obstruction in infants is about 50 per 100,000 infants. …