Viral hepatitis has been known to occur among the Greenland population endemically as well as in smaller and larger epidemics. A large epidemic of acute hepatitis comprising around 9% of the entire population, viz. more than 4000 notified cases, swept through Greenland between October 1970 and December 1972. 996 verified cases were seen in the Godthaab district and subjected to more detailed studies. Most of the Godthaab cases were seen among children and adolescents, and no disease was observed in children less than one year of age. Out of 996 diagnosed cases 9 showed acute hepatic failure with coma. Two further cases of hepatic coma were referred for treatment from outside the district. Three of these 11 patients recovered spontaneously. Of the residual 8 cases 6 were treated with exchange transfusions and steroids. Four of these survived and recovered completely. No lasting sequelae had been registered in any of the surviving cases of the epidemic up to June 1975 (2 1/2 years after cessation of the epidemic). Prophylaxis with gamma-globulin was undertaken in a medium-sized settlement in which practically the entire population received gamma-globulin when the first case of hepatitis was diagnosed. In this settlement only 7 out of 297 inhabitants contracted hepatitis. By contrast, in a similar settlement where no gamma-globulin was given, more than 30% of the population developed icteric hepatitis. The clinical features and the prophylactic effect of gamma-globulin seem to indicate that the epidemic was caused by the hepatitis A virus. In accordance with this, transitory Australia-antigenaemia was demonstrated in the acute phase in only 2.6% of the cases, possibly inidicating a small admixture of acute hepatitis type B to the epidemic predominantly caused by hepatitis A virus.
985 episodes of hepatitis representing 98% of all acute hepatitis episodes found in a Swedish city during a 10-year period were analyzed for anti-hepatitis A IgM antibodies and hepatitis B surface antigen. Hepatitis A was diagnosed in 311 episodes (32%), hepatitis B in 494 (50%), simultaneous acute hepatitis A and B in 12 (1.2%), and 168 episodes (17%) were classified as hepatitis non-A, non-B. The majority of the hepatitis A cases were drug addicts (58%), and all were concentrated in 3 outbreaks of 1-2 years duration. 16% of all hepatitis A cases were probably imported. Hepatitis B cases decreased significantly (p less than 0.001) between the first and second half of the study period. 47% were drug addicts. Hepatitis non-A, non-B was also dominated by drug addicts (61%). Approximately 20% of the cases in all 3 types of hepatitis had no identifiable source.