An Epidemiologic Investigation on an Outbreak of Anthrax Occurred in Kyongju by Eating Dead Cow's Meat

경주시 배반동에서 발생한 탄저병에 관한 역학조사

This epidemiologic study was carried out to investigate cauuse and magnitude of food-poisoning like epidemic occurred among inhabitants of a village who have eaten dead cow's meat near Kyongju in February of 1994, around lunar new year, The investigation consisted of interview survey on all inhabitants of 77 households (111 males and 119 females) and their visitors (40 males and 35 females), skin test with anthraxinum (Russian product), study on clinical characteristics for the patients hospitalized, and microbiologic examination on microbes isolated from cow's meat, patient and soils of dead cow's barn. The results obtained are as followings; 1. The proportion of the inhabitants who ingested the dead cow's meat was 36.4%. The incidence rate of the disease was 65.1% for males, 41.7% for females and the cases were distributed evenly for all age groups. The group ingested raw meat showed higher incidence than the group ingested cooked meat. There was no case among people who did not eat the meat. 2. The most clinical symptoms were significantly more frequent among cases than non-cases : sore throat (57%), nausea (51%), fever (47%), indigestion (43%), cough (41%), anorexia (41%), abdominal distention (41%), and abdominal pain (39%) were the major symptoms among cases. 3. Among 29 cases hospitalized out of total 61 cases, three patients, all old and feeble persons, deceased from the disease resulting in 4.9% fatality rate among total patient and 10.3% among hospitalized. Septicemia and meningitis were the causes of the deaths. 4. Three strains isolated from patients, and three strains from dead cow's meat and soil revealed typical microbiologic characteristics of Bacillus Anthracis, which also proved to be fatal to experimentally infected mice.