title: Intensive hepatitis surveillance in Minnesota: methods and results.
abstract: After a large foodborne outbreak of hepatitis A in April 1974, the Minnesota Department of Health attempted to improve ongoing hepatitis surveillance with a system based on 1) a large centralized blood bank, which reports results of tests for hepatitis B surface antigen (HBsAg) on suspected hepatitis patients; 2) private physicians, who are encouraged to report cases; and 3) an epidemiology aide, who contacts all detected patients and their physicians. During the first year of this system, we detected 932 cases (24.5 per 100,000), a threefold increase over previous years, and obtained detailed epidemiologic data on each case. Although physicians diagnosed 61% of these cases as hepatitis A (or non-B) and 39% as hepatitis B, they tested only 53% of all patients for HBsAg. Sixty-seven per cent of the tested patients were HBsAg-positive, but only 17% of the untested patients had illnesses diagnosed by physicians as hepatitis B. This suggests that many patients with clinically-diagnosed viral hepatitis who are not tested for HBsAg may be erroneously diagnosed by physicians as having non-B hepatitis. Thirty-three per cent of HBsAg-positive patients with known occupations, not including housewives and students, worked in meidcally-related occupations. For 51% of the HBsAg-positive patients, we could not identify recent parenteral exposure to hepatitis B.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks / Q000453:epidemiology; D005260:Female; D006506:Hepatitis A / Q000453:epidemiology; D006509:Hepatitis B / Q000453:epidemiology; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006525:Hepatitis, Viral, Human / Q000453:epidemiology* / Q000276:immunology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D008910:Minnesota; D009790:Occupations; D011159:Population Surveillance; D012737:Sex Factors
chemical_list: D006514:Hepatitis B Surface Antigens