How to eliminate taeniasis/cysticercosis: porcine vaccination and human chemotherapy (Part 2)

Abstract

Background The application of effective vaccines against pig cysticercosis and mass chemotherapy against pig cysticercosis and human taeniasis have shown the feasibility of interrupting the parasite’s life cycle in endemic areas. Methods A mathematical model that divides the population into susceptible, infected, and vaccinated individuals is formulated. The model is based upon the life cycle of the parasite. Computer numerical simulation experiments to evaluate the impact of pig vaccination under different vaccination schedules, and combined intervention strategies including pig vaccination and anthelmintic treatment against human taeniasis are carried out. Results Vaccination against either pig cysticercosis or against human taeniasis will influence the transmission dynamics not only among vaccinees but also the dynamics of the other hosts as well. When the protective efficacy and/or the coverage rate is less than 100%, different mass interventions like vaccinating the pig population twice in combination with chemotherapeutic treatment against human taeniasis, the elimination of the infection in both pigs and humans can also be achieved. Conclusions Our mathematical model has the potential for planning, and designing effective intervention strategies including both mass vaccination and/or chemotherapeutic treatment to eliminate pig cysticercosis, human taeniasis and human neurocysticercosis. The model can be adapted to any given community with mild, moderate endemicity, or even in hyperendemic regions. Electronic supplementary material The online version of this article (10.1186/s12976-019-0100-x) contains supplementary material, which is available to authorized users.

Use of Veterinary Vaccines for Livestock as a Strategy to Control Foodborne Parasitic Diseases

“…Humans are the only definitive host of T. solium and acquire taeniasis (the adult tapeworm infection) eating raw or undercooked pork containing cysticerci (the larval form of T. solium ). In turn, they will shed eggs of T. solium in their stool, which if ingested by other (or the same) humans or pigs (the usual intermediate host) will lead to the development of cysticerci (Sánchez-Torres et al, 2019 ). Deficient levels of sanitation as well as pig husbandry practices and eating habits conditionate the prevalence of T. solium infection in a determinate region (World Health Organization, 2014 ).…”

Modelling for Taenia solium control strategies beyond 2020

“…However, technical definitions of both intensified control and hyperendemicity need clarification for progress towards these goals over the next decade to be effectively evaluated. A key modelling activity should involve predicting, in a variety of epidemiological settings, the effect of various interventions in the currently available set • yes, if realistic control targets are proposed • modelling can inform the design and evaluation of pilot and large-scale control programmes with current and complementary intervention strategies 8,13 • cystiSim and EPICYST, computational transmission models, are applicable; 17,18 cystiSim is already in use in Zambia and Latin America, and an additional transmission model has also been developed for Latin America 23,24 What is required to achieve the target?…”

Impact of a 3-year mass drug administration pilot project for taeniasis control in Madagascar

“…In the case of T. solium, the impact of taeniasis treatments alone as a control measure is hampered by the continued existence of infections in the pig population which serve as a source for re-establishment of taeniasis in humans. Mathematical modelling of T. solium transmission and its control [31][32][33][34], and a logical model of T. solium control [35], suggest that a combination of interventions in the pig population (vaccination and medication) as well as MDA application of taeniacide in humans would have a more rapid, more substantial and longer lasting impact on T. solium transmission than the use of taeniacides alone. The treatment of human taeniasis, and the interventions in pigs are described as core "rapid impact" interventions, but other supportive measures such as improved sanitation, community education, pig husbandry and meat inspection can also play an important role [36].…”