Seven outbreaks of trichinosis in China [1992-1996]

ABSTRACT

Seven outbreaks of trichinosis occurred in Zhengzhou [Central China]. From 1992 to 1996, 250 patients were diagnosed. Trichinella larvae were found in 3 of 4 portions of the pork examined and in 5 of 7 cases by muscle biopsy. There was a higher occurrence of outbreaks in winter. Young and middle-aged workers, cadres and merchants were the majority of patients [higher in males than in females]. The most important clinical manifestations were fever, eyelid edema, tiredness and eosinophilia without any gastrointestinal symptoms, rash and with less myalgia. Anti-trichinella antibodies were detected by IF in 62.6% of individuals with the history of infection. The specific antibodies were only observed in 78% of patients one week after onset of disease, while the antibody positive rate was increased to 92.5%, 97.6% and 100% at 2, 3, 4 and 5 weeks after onset and evidently increased from 89.6% before therapy to 100% at 1 week after therapy, then decreased to 74.6% and 23.7% at 1 and 4 months after therapy, respectively. This suggested that IF is a useful tool for immunodiagnosis and checking up the therapeutic effect of trichinosis