Food Safety and Regulatory Aspects of Cattle and Swine Cysticercosis

Using slaughter disposition data maintained by the Food Safety and Inspection Service (FSIS) of the U.S. Department of Agriculture, prevalence of cattle cysticercosis (Cysticercus bovis) for a 10-year period from 1985 through 1994 is reported. Out of an annual average of approximately 33 million slaughtered cattle, about 6,200 carcasses were identified with cysticercus lesions. In the five FSIS inspection regions in the United States, namely Western, Southwestern, Northeastern, Southeastern, and North Central, an average cattle cysticercosis prevalence of 0.0697, 0.0085. 0.0012, 0.0004, and 0.0003, respectively, is reported. The relevance of serological testing in lieu of, or as a supplement to, the current labor-intensive physical detection procedure in cattle is discussed, the latter being reported to miss close to one-third of the carcasses harboring cysticercus lesions. Out of a total of approximately 80 million swine slaughtered annually in the United States, the number of carcasses identified with cysticercus lesions (Cysticercus cellulosae) is extremely low, ranging from I through 44 during each of the 10 years. Swine cysticercosis (unlike cattle cysticercosis), with man being an alternate intermediate host, poses serious public health concerns with sometimes fatal consequences manifested through neurocysticercosis (Cysticercus cellulosae). Though human cysticercosis is still rare in the United States, recent reports have indicated an upturn in diagnosed cases. These are primarily the result of an increasing number of immigrants and international travel to and from endemic areas.