Childhood Survival in Haiti: Protective Effect of Measles Vaccination

Abstract

To evaluate the impact of measles vaccination on survival of children residing in a periurban slum in Haiti, a total-population survey was conducted 2.5 years after completion of a one-time study of the serologic response to measles vaccine administered in the same population. Pregnancy histories from the 16 400 women in the population revealed that 1499 children had been born during a 7-month interval that would have made them eligible for participation in the measles vaccine program. Of these children, 1381 (92.1%) survived to 9 months of age, the median age that measles vaccine had been administered. Seventy-three infants had died between 9 and 39 months of age. Mortality of infants who were seronegative before receiving measles vaccine was significantly lower (P = .0013) than that of unvaccinated infants (3/235 vs 70/1056, respectively). Other factors positively associated with survival between 9 and 39 months of age included socioeconomic status (P = .0002), maternal literacy (P = .0020), maternal knowledge and use of oral rehydration solution (P = .0002), and an interval of greater than 24 months to the birth of the next younger sibling (P = .0012). Multivariate stepwise logistic regression analysis was used to evaluate the independent association of measles vaccination by adjusting for other factors that also correlated with survival and that might have been associated with maternal seeking of vaccinations. Children who survived were more likely to have received measles vaccine than children who died, independent of the effects from socioeconomic status, maternal knowledge of oral rehydration solution, maternal literacy, and birth interval (adjusted odds ratio = 6.5, 95% confidence interval 1.6 to 27.1). Estimates of the efficacy of measles vaccine for prevention of mortality from 9 through 39 months of age ranged from 84.7% to 90% by different methods of analysis. Therefore, measles vaccination appears to be an effective intervention for improving the survival of children residing in developing countries. Efforts should be increased to eliminate this disease from all countries.