RESUMO: A esquistossomose é uma importante doença transmitida por vetor, um hospedeiro intermediário: um molusco de água doce. O controle desses caramujos vetores é uma das estratégias da Organização Mundial da Saúde para controle da doença. O presente estudo foi baseado em uma revisão sistemática de artigos científicos publicados sobre o controle biológico de caramujos (gênero Biomphalaria), e teve como objetivo identificar os desafios atuais e propor perspectivas futuras. A metodologia de revisão foi baseada na declaração PRISMA, nas bases de dados internacionais, Web of Science e Scopus, entre 1945-2021. No total, foram analisados 47 artigos, publicados por autores de 14 países diferentes, sendo a maioria: França, Brasil, Estados Unidos e Egito. A estratégia mais utilizada para controle biológico foi a predação por peixes (12 estudos). Quatorze artigos foram publicados na década mais produtiva 2010-2019, durante a qual também houve uma maior diversidade de agentes de controle biológico em estudos. Neste contexto, acreditamos que um dos principais desafios desta abordagem é a utilização simultânea bem-sucedida de múltiplos tipos de agentes de controle biológico: predadores, concorrentes e/ou agentes microbianos. Esta nova abordagem fornece importantes subsídios para o desenvolvimento de novos agentes de controle biológico ou produtos de base microbiana, com o potencial de reduzir a carga parasitária transportada pelo vetor esquistossomose de caramujos e controlar sua transmissão de forma sustentável.

ABSTRACT: Schistosomiasis is an important vector-borne disease transmitted by an intermediate host: a freshwater mollusk. Control of these snail vectors is one of the strategies of the World Health Organization against the disease. The present study was based on a systematic review of published scientific papers concerning the biological control of snails (genus Biomphalaria), and identified the ongoing challenges and propose future perspectives. The review methodology was based on the PRISMA statement, the international databases Web of Science and Scopus for the period 1945-2021. In total, 47 papers were analyzed, published by authors from 14 different countries, the majority being from: France, Brazil, the United States, and Egypt. The most widely used strategy for biological control was predation by fish (12 studies). Fourteen papers were published in the most prolific decade 2010-2019; during which there was also a greater diversity of biological control agents in studies. In this context, we believed that one of the principal challenges of this approach is the successful simultaneous use of multiple types of biological control agent: predators, competitors, and/or microbial agents. This new approach may provide important insights for the development of new biological control agents or microbial-based products, with the potential to reduce the parasite load carried by schistosomiasis snail vector and control its transmission in a sustainable way.

Abstract Schistosomiasis is a neglected tropical disease and affects over 200 million people worldwide. The snail Biomphalaria glabrata is one of the intermediate hosts of S. mansoni. The aim of this work was to verify the action of Euphorbia milii var. hislopii latex in the hemocytes profile and histopathology of B. glabrata infected by S. mansoni. Uninfected and infected snails were exposed to sublethal concentration of E. milii latex for 24 hours (1.0 mg/L). The survival rate was 88.5% for the uninfected snails and 66.6% for the infected and exposed snails. In the snails infected by S. mansoni, the exposure to E. milii latex promoted proliferation of hemocytes in the tentacles, mantle, digestive gland and kidney. In the digestive gland and the kidney, granulomatous reactions occurred around the sporocysts and caused their destruction. The number of circulating hemocytes from the group infected and exposed to E. milii latex was significantly higher than in the other groups. Three types of hemocytes were found: hyalinocytes, granulocytes and blast-like cells. We conclude that the E. milii latex influenced the cellular immune response of the susceptible B. glabrata strain to infection by S. mansoni, promoting the destruction of parasites.