Mass chemotherapy for intestinal Taenia solium infection: effect on prevalence in humans and pigs

Abstract

Mass treatment of the human population with niclosamide was carried out in 2 villages in rural Guatemala where Taenia solium was endemic, to determine how this would affect the epidemiology of the parasite. Intestinal taeniasis was diagnosed by microscopy and coproantigen testing, and porcine cysticercosis by a specific Western blot. Before mass treatment, the prevalence of human taeniasis was 3.5%; 10 months after treatment it was 1%, a significant decrease (P < 10(-4)). All tapeworms that could be identified to the species level were T. solium. Similarly, the seroprevalence of antibodies to cysticercosis in pigs declined from 55% before treatment to 7% 10 months after treatment, once again a significant decrease (P < 10(-6)). These effects were seen in both villages. The possible use of mass chemotherapy as a tool in the control of T. solium is discussed.

Hyperendemic Human and Porcine Taenia Solium Infection in Perú

“…In this series, the age-prevalence curve of intestinal taeniasis peaks at an earlier age than do human cysticercosis antibodies. This would not support the classic theories of a long tapeworm life span of 20 years and corroborates recent studies in Guatemala 18,22,23 which suggested that the life span is much shorter than suspected, probably below 5 years in most cases. Symptomatic neurocysticercosis is known to appear years after exposure.…”

Prevention and control ofTaenia soliumtaeniasis/cysticercosis in Peru

“…Mass human chemotherapy has been tested in several countries. [48][49][50][51] In general, the result was a decrease in prevalence of porcine cysticercosis and human taeniasis. The scarce data available in regards to the sustainability of its effect suggests that transmission will very quickly recover after chemotherapy is stopped.…”

The Parasitological, Immunological, and Molecular Diagnosis of Human Taeniasis with Special Emphasis on Taenia solium Taeniasis

“…Such low sensitivity is primarily due to the intermittent nature of egg release, which leads to an underestimation of the prevalence of taeniasis [43]. Allan et al [44] reported that coproscopic studies from patients with active tapeworm infection are commonly negative because, firstly, eggs may not appear in feces every day, and secondly, eggs are not uniformly distributed in feces. For these reasons the authors recommended the collection of samples over a three-day period.…”

“…Furthermore, coproantigens are not detectable after treatment and the antigens are stable in fecal samples [31] making the test very useful for the early detection and evaluation of antiparasitic treatment efficacy in human T. solium taeniasis [51]. In epidemiological studies, the coproantigen ELISA is reported to detect around 2.5 times more cases of taeniasis than basic microscopy [42,44].…”