Past and Future Methods for Controlling Echinococcus granulosus in South America

POGGIO T V; JENSEN, O; SARAVIA, T; NUÑEZ, A; BOADO L; GOMEZ J M; HEATH, DAVID

international journal of echinococcoses

Effect Publishing Agency

Lugar: Karsiyaka Izmir; Año: 2022 vol. 1 p. 26 - 71

2822-3152

The various Countries of South America (Peru, Brazil, Chile, Uruguay, Argentina) all have problems with Echinococcus granulosus s.l in humans. Control of the disease in dogs and grazing animals began in Uruguay in 1879, and continues in all countries from various beginnings until 2022. Our objective is to describe the new vaccine to prevent grazing animals from acquiring E.granulosus s.l., and to predict the possible high degree of control using the addition of the vaccine to the normal control procedures even when programmes address many practical difficulties.The recombinant vaccine was used under field conditions using the same protocol in sheep, goats and llamas older than 2 months and up to 6 years: Two injections, one month apart and annual booster. The baseline and the final evaluation were carried out by necropsy in control programmes included in Argentina (Chubut, 2007-2013; Río Negro 2009-2017) and in Chile (Alto Biobio, 2016-2020; Aysen 2020-2022).Elimination of echinococcosis have been successful only in insular countries. In consequence, to validate a model supporting the One Health approach that might be reproducible successfully in different regions of South America is required. Including the socio-cultural understanding and the environmental context is mandatory to optimize the use of the vaccine under these operational conditions.The EG95 vaccine, made in Argentina, has been tested, and continues to be tested, in Argentina and Chile, and more recently in Peru. Furthermore, the vaccine, now available, is being made in large quantities in Argentina and China, and appears to be an additional control technology that may allow elimination of E.granulosus s.l. from South America. The best control strategies appear to be dog treatments and regular vaccination of sheep and goats for 10 years until all old sheep have been removed. If dogs or grazing animals enter from outside the controlled environment, treatments will need to be continued. The vaccine also seems to reduce E.granulosus s.l. cysts reaching infectivity for dogs, and has some effect against Fasciola hepatica.