[Trichinosis outbreak in Purranque County, X Region, Chile. October-November, 1992].

An outbreak of trichinosis occurred in Purranque County, X Region, Chile, between october and november of 1992, which involved 36 persons. The incubation period, determined by the clinical picture and laboratory assays, fluctuated between 10 and 12 days. Myalgias (88.9%) and palpebral oedema (86.1%), were the most important symptoms, followed by fever (44.4%) and headache (33.3%). Eosinophils count ranged from two to 42% the first week, and this value raised to 55% the second week of the outbreak. Anti-Trichinella spiralis antibodies were determined by some serological tests such as: precipitin test (PT), bentonite flocculation test (BFT) and indirect hemagglutination test (IHAT) in sera from 28 patients at the beginning of the outbreak. PT was positive in 46.4% of the cases, followed by IHAT (21.4%) and BFT (3.6%). After 15 days, the three tests were performed in sera from 12 patients. At that time, the positivity was elevated in all of them: PT (100.0%), BFT (66.7%) and IHAT (91.7%). It is believed that the outbreak had its origin in infected pork meat that was consumed raw or insufficiently cooked without a previous veterinary inspection.