To determine the prevalence of cysticercosis in a rural area where the disease is endemic, the authors studied the seroepidemiology of human and porcine cysticercosis in a Peruvian jungle community (Maceda, Peru) in 1988 using an enzyme-linked immunoelectrotransfer blot (EITB) assay. Of the 371 sampled inhabitants, 30 (8%) were seropositive, most of whom were asymptomatic. After niclosamide therapy, four Taenia species worms were identified in the seropositive group, compared with one in the control group (p = 0.06). Pigs were frequently infected: 44 of 133 (33%) were found positive for Taenia by tongue examination and 57 of 133 (43%) were positive by EITB. In 69% of the sampled households that had pigs, there was at least one seropositive pig. The number of pigs diagnosed positive by the tongue examination was significantly greater in households that had latrines than in those that did not. Cysticercosis is a common but usually asymptomatic infection that affects both humans and pigs in the high jungle areas of Peru. Keywords cysticercosis; environmental monitoring; immunoblotting; swine; Taenia; toilet facilities; transfer blot Cysticercosis is a disease endemic in most developing countries where pigs are raised (1). In both Mexico and Peru, more than 10 percent of neurologic patients receiving acute care have serologic evidence of Taenia solium infection (2, 3). Humans acquire cysticercosis by ingesting T. solium eggs from human feces either directly or indirectly, through contaminated food or water. The eggs mature into larvae, which invade the intestinal wall, Copyright © 1992
Europe PMC Funders Author ManuscriptsEurope PMC Funders Author Manuscripts muscle, brain, and other tissues. Pigs also acquire cysticercosis in the same manner. Humans develop taeniasis after ingesting raw or poorly cooked pork or beef that contains the larval form of T. solium or Taenia saginata. Larvae invaginate the small intestine of humans and develop into adult tapeworms. The tapeworm produces eggs after 3 months and may survive for years, thus spreading cysticercosis in both humans and pigs (4, pages 609-25).Rational programs to control cysticercosis cannot be developed until the epidemiology of the disease is better understood. The true incidence of cysticercosis in both human and pig populations is unknown. The prevalence of porcine infection, based on meat inspections in Mexican slaughterhouses, has been estimated at 0.005-10 percent (5). However, many infected pigs are raised by small farmers, who often sell their pigs in informal markets where meat inspection is not performed. Since governmental and international agencies base their statistics for porcine cysticercosis on slaughterhouse statistics (6, 7), clandestine sale of meat results in a considerable underestimation of the true prevalence rates of porcine cysticercosis. For example, in Huancayo, a city of 500,000 inhabitants in the highlands of Peru, no pigs were registered as infected with cysticercosis (8), yet field surveys revealed that more than 30 per...