Delayed measles mortality among exposed children who survived the epidemic of 1714–15 in New France

This follow-up study examines delayed mortality of children under age 5 who were exposed to measles and survived the acute phase ofthe 1714–15 epidemic in Quebec. The objective of the study was to assess whether exposed children had higher long-term mortality thanunexposed children, by following them for 25 months past the estimated date of infection. Overall, children exposed before age 3 had higher long-term mortality than unexposed children. The difference remained significant while assessing other risk factors. Delayed mortality also varied by age and sex. Only exposed female infants had a significantly higher risk of dying, while both exposed male and female toddlers had higher mortality. No significant difference was found among children exposed after age 3. Findings are explained in terms of modern post-measles studies in Africa and of previous measles studies in New France.