In March, the FDA advised against the use of GSK’s Rotarix vaccine against the rotavirus — a gastrointestinal virus that kills over half a million children under five worldwide each year — after researchers found trace amounts of DNA from a benign pig virus in the vaccine. Recently, the only other rotavirus vaccine, Merck’s RotaTeq, was found to contain DNA from the same virus and another virus. So far, similar warnings against RotaTeq have not been issued, and the FDA is expected to release updated recommendations soon.
“The original virus found in Rotarix, known as PCV1, does not even cause sickness in pigs, much less humans,” says Dr. Ross. “PCV1 was also found in RotaTeq, along with PCV2, which can cause sickness in pigs, but is still harmless for humans. The risk from either vaccine is likely nonexistent, as opposed to the real risk from rotavirus infection. But, like many regulatory agencies, the officials at the FDA are very reluctant to admit that they made a mistake. It seems quite clear that the benefits of both vaccines far outweigh the risks, especially in underdeveloped countries where the rotavirus takes its greatest toll.”