In the United States, people become infected by eating poorly cooked pork products or wild animal meat that is infected with the parasite. Although fewer than 100 cases per year are reported to CDC, trichinosis continues to persist as a public health problem in this country. Public health officials believe that the reported cases represent only a fraction of the total number of cases, since many of the mild or asymptomatic infections are undetected or are misdiagnosed unless they are related to more severe cases. In 1986, commercial pork products accounted for only three isolated cases of trichinosis. The other cases of trichinosis caused by pork included wild boar or pork purchased directly from a farm.
Trichinosis is a preventable disease.
In the period 1977-1981, the average number of reported cases per year was 137. In 1982-1986, this figure dropped to 57 cases. No apparent change in the surveillance system can account for this downward trend. Additional cases are identified through reported results of trichinosis serologic tests performed by the Parasitic Diseases Branch, DPD, and through investigations conducted by the DPD staff. Trichinella-positive muscle biopsy or positive serologic test for trichinosis in a patient with one or more clinical symptoms compatible with trichinosis, such as eosinophilia, fever, myalgia, and periorbital edema, or 2.