Aspects of clinical features, diagnosis, notification and tracing back referring to Trichinella outbreaks in north Rhine-Westphalia, Germany, 1998.

52 cases of human trichinellosis were notified from 11 towns in North Rhine-Westphalia from November 1998 to March 1999. After non-typical symptoms in the enteral phase, fever, muscular ache, headache, oedema, disorder of vision and rash occurred in the parenteral phase. Trichinellosis was serologically confirmed by ELISA, IFAT or western blot. Raw sausage and minced meat produced from raw pork could be determined as probable source of infection with 44 and eight notified cases, respectively. Whereas questionable raw sausage was not available for examination, frozen minced meat from the second outbreak could be secured in households of infected people. Larvae were isolated from minced meat and were identified by PCR as Trichinella spiralis. Tracing back to the source of infection was difficult because of the long time between clinical symptoms, laboratory diagnosis and notification as well as complex trade routes for pork and its products. Trichinella cases emphasize the necessity to meet the prescribed slaughter inspection and to guarantee a reliable prove of origin for meat products especially in view of specific consumer habits, i.e. the consumption of raw meat.