Persistent rubella infection and rubella-associated arthritis.

Rubella virus has been isolated from peripheral blood lymphocytes in six out of seven women with rubella-associated arthritis. The arthritis occurred after natural infection (one case) or immunisation with HPV 77 DES vaccine (six cases) and had been present for up to 6 years. The identification of rubella virus was confirmed by plaque/microfocus reduction in the presence of anti-rubella antiserum, and by immunoprecipitation of rubella virus antigens and their analysis on polyacrylamide gels. These women with rubella virus in their lymphocytes did not have abnormal serum antibody levels, but a standard lymphoproliferative assay showed that they had strong cell-mediated immune responses to rubella virus antigens.