IGG AND IGM ANTIBODIES AGAINST MEASLES-VIRUS IN UNVACCINATED INFANTS FROM PUNE - EVIDENCE FOR SUBCLINICAL INFECTIONS

IgG and IgM class of antibodies to measles virus were estimated in the plasma samples of 211 unvaccinated infants living under overcrowded c onditions in Pune, Maharashtra. IgG antibodies to measles virus, in hi gh titres, were detected in 52.1 per cent and IgM antibodies in 31.3 p er cent of the infants studied. Most of the infants with IgM antibodie s to measles virus had not suffered from an attack of measles. A histo ry of contact with an older child with overt measles was available for 13.3 per cent of the 211 infants studied. Among these infants with su ch a contact history, 82.1 per cent had IgM antibodies to measles viru s. These observations suggest that many infants studied by us, had exp erienced subclinical measles infections and many times older children with measles at home or in the neighbourhood might have transmitted su ch infections.