vaccine-associated demyelination and cell-mediated responses to measles virus antigens and myelin basic protein.
As mentioned earlier, Landrigan and Witte (1973) used data voluntarily submitted to the Centers for Disease Control regarding neuralgic disorders following administration of measles vaccine. From 1963 to 1971, 84 cases of neuralgic disorders with onset of less than 30 days after administration of live measles vaccine were reported in the United States. One of the case patients was diagnosed as having transverse myelitis. No further information was provided.
VAERS contains one report (submitted between November 1990 and July 1992) of transverse myelitis developing shortly after MMR vaccination alone and one after MMR given in conjunction with DPT, oral polio vaccine (OPV), and Haemophilus influenzae type b (Hib) vaccine. The temporal and clinical details in those reports are insufficient for proper evaluation.
There is demonstrated biologic plausibility for a causal relation between measles vaccine and transverse myelitis, in that measles virus is well associated with demyelinating disorders. Two cases of transverse myelitis following administration of measles vaccine and two cases following administration of MMR were identified. These cases were temporally associated with administration of the vaccine; there was no other evidence that associated the vaccine and the adverse event. No data from observational or experimental studies lend support to the hypothesized association. The incidence of transverse myelitis unrelated to vaccine is estimated to be about 1 case per 100,000 population (Beghi et al., 1982). Thus, the number of cases identified do not appear to be above background rates, and any study designed to detect an excess number of cases over the background would have to be very large.