Vaccination causing intussusception: (PGI Dec 2007)

Ans: A (Rota virus) Harrison 17th / 778;Writes# Within 9 monthsof its introduction, cases of intussusception were reported by the CDC to be temporally associated with the administration of the initial vaccine dose. This report led first to the cessation of the vaccine's use and subsequently to its withdrawal from the market and the discontinuation of its production.# The withdrawal of the vaccine in the United States made its use impossible in developing countries, where the risk of any increase in intussusception would have been dramatically outweighed by the benefit of decreased rotavirus mortality rates. It is now apparent that the susceptibility to intussception is age related, with virtually no events in children <90 days of age.# Almost a decade later, a new rotavirus vaccine has been licensed in the United States and recommended for routine use beginning at <2 months of age. In the interim, some 4-5 million infants have died of rotavirus diarrhea in the developing world; most of these deaths could have been prevented by the original rhesus rotavirus vaccine. "virus vaccine was taken off the market when a strong epidemiological link between application of the first (and second] dose of the vaccine and the development of gut intussuception' became apparent" - Greenwood Microbiology 16th/526