Eleven patients (nine men, one woman, and one girl) aged 11-62 years who developed diabetes mellitus after an attack of infectious hepatitis during the Eastern Nigerian epidemic of 1970-2 were followed up for two to nine years. One patient aged 60 years remained diabetic after the original illness. In the remaining 10 patients the diabetes remitted after three to nine months (mean 6.7 months) but in four it recurred after a remission lasting one and a half to four years (mean 2.6 years). Results of this follow-up study seem to confirm that the pancreas is sometimes permanently damaged during infectious hepatitis.