Has the Measles-Mumps-Rubella Vaccine Been Fully Exonerated?

Abstract

Initiated by a report in 1998 by Wakefield et al1 that the onset of a syndrome of ileal-lymphoid-nodular hyperplasia and nonspecific colitis accompanied by pervasive developmental disorder had appeared shortly after receipt of measles-mumps-rubella (MMR) vaccine by 8 children, the vaccine was soon indicted as the etiology of autism spectrum disorders (ASDs). Subsequent reports elaborated on this theory, and several laboratories claimed to have detected measles virus or its genome in intestinal biopsies as well as peripheral blood mononuclear cells from such autistic children.2–4 Other reports described elevated levels of measles antibodies in children with autism.5 In this issue of Pediatrics , D’Souza et al6 present their detailed, careful laboratory studies that refute these claims and explain the errors that led to them. Within a short time after the initial report by Wakefield et al, many parents in the United Kingdom and the United States opted to refuse the MMR vaccine for their infants and children. One explanation offered by the original reporters was that simultaneous MMR vaccination might lead to an aberrant immune response resulting in persistent infection and increased permeability of an inflamed gastrointestinal tract. Such conditions permitted the transport of opiate-like peptides to the central nervous system resulting in the autism syndromes.7 These claims occurred at a time of recognition that reports … Address correspondence to Samuel L. Katz, MD, Duke University Medical Center, Division of Pediatric Infectious Disease, Box 2925, Durham NC 27710. E-mail: katz0004{at}mc.duke.edu