Clinical safety issues of measles, mumps and rubella vaccines

The clinical safety of measles and measles-mumps-rubella vaccines has been questioned in recent reports that propose a possible link between measles v irus or measles vaccines and the occurrence of juvenile Crohn disease and a utism. This article reviews the outcomes of several laboratory investigatio ns which were carried out independently to identify the presence or absence of measles virus in the intestinal tissues derived from cases of inflammat ory bowel disease. One research group reported the presence of measles viru s particles and genomic RNA in inflammatory bower disease tissues, but this could not be confirmed by other groups, despite use of techniques that are highly specific and sensitive for the detection of measles virus nucleic a cid in clinical specimens down to the molecular level, Based on the publish ed data reviewed here, it can be concluded that there is no direct associat ion between measles virus or measles vaccines and the development of Crohn disease, a conclusion which is supported by most epidemiological findings.