Mortality due to Reye's syndrome in Michigan: distribution and longitudinal trends.

Death rates due to Reye's syndrome and related diseases among children in Michigan were estimated from 1969 to mid-1977 on the basis of searches of death certificates, with verification of diagnosis by review of hospital records. There was no significant increase in mortality for Reye's syndrome during the study period. Temporal association with type A and B influenza outbreaks was found. The syndrome occurred at a lower rate in summer and autumn when these infections, as well as chickenpox, were rare. The mean age of children dying of Reye's syndrome and related diseases was 5.5 years, with a modal age of less than one year. Deaths among white children were more frequent than among black children, but below the age of one year the reverse was true. In black children a higher mortality was found among males than among females. Deaths due to Reye's syndrome were more common in rural areas than in urban areas.