Severe measles in Sunderland, 1885: a European-African comparison of causes of severe infection.

On the basis of research in Guinea-Bissau, this paper re-analyses a severe measles epidemic which occurred in 1885 in Sunderland (England). In both England and Guinea-Bissau, acute measles mortality was higher in households with multiple cases than in families with only a single case of measles. Secondary cases (infected in the house) had higher mortality and higher frequency of severe complications than index and single cases. In Sunderland, severe complications were associated with a history of previous respiratory infection and with greater number of siblings. Since cases with severe complications had significantly prolonged prodromal symptoms and shorter periods of incubation, it is suggested that high dose of infection may be an essential mechanism in the pathogenesis of severe disease. Overcrowding may be a major determinant of severe measles because it increases the risks of intensive exposure, intercurrent infections, and previous respiratory infection.