Non-specific beneficial effect of measles immunisation: analysis of mortality studies from developing countries

OBJECTIVE: To examine whether the reduction in mortality after standard titre measles immunisation in developing countries can be explained simply by the prevention of acute measles and its long term consequences. DESIGN: An analysis of all studies comparing mortality of unimmunised children and children immunised with standard titre measles vaccine in developing countries. STUDIES: 10 cohort and two case-control studies from Bangladesh, Benin, Burundi, Guinea-Bissau, Haiti, Senegal, and Zaire. MAIN OUTCOME MEASURES: Protective efficacy of standard titre measles immunisation against all cause mortality. Extent to which difference in mortality between immunised and unimmunised children could be explained by prevention of measles disease. RESULTS: Protective efficacy against death after measles immunisation ranged from 30% to 86%. Efficacy was highest in the…