Non-use and misuse of measles vaccine.

During a major epidemic of measles in 1970-71 in Hamilton, Ont., 86 percent of hospitalized patients were unimmunized; 57 percent of these children had complications. Of those immunized, the majority had inadequate protection because killed measles vaccine had been used, or because immunization had taken place before 12 months of age. Only 90.5 percent of responding physicians use mv routinely, and of these a significant number administer the vaccine before 12 months of age. One-third of the physicians felt that cost was a major factor in non-immunization. Physician office records could give no reason for non-immunization in 58 percent of cases; other reasons included change of physicians with inadequate transfer of records, previous history of measles or measles vaccine (both likely German Measles - i.e. a semantic confusion), and lack of parent compliance. It is suggested that government legislation making proof of mv mandatory prior to school entrance may be necessary to eradicate this disease.