Introduction: Angiostrongylus cantonensis causes eosinophilic meningoencephalitis in humans. Worldwide expansion of this nematode is linked to the dispersion of their hosts. This study aimed to determine the prevalence of A. cantonensis infection in Achatina fulica in the nine municipalities that make up Baixada Santista, São Paulo, Brazil. Methods: Angiostrongylus cantonensis larvae were analyzed using optical microscopy. We performed polymerase chain reaction and restriction fragment length polymorphism using restriction endonuclease ClaI, directed to the internal transcribed spacer region 2 of A. cantonensis larval DNA. Results: Of the 540 snails analyzed, 117 (21.7%) were infected by A. cantonensis. For morphological and morphometric analyses, 60 larvae were used. Second-stage larvae were, on average, 358.2µm long and 26.4µm wide, while third-stage larvae were, on average, 450µm long and 21.12µm wide. The tails of the larvae ended in a fine tip. Conclusions: All municipalities comprising Baixada Santista had A. fulica that were naturally infected with A. cantonensis. All of the observed characteristics were typical of the species.

The easy adaptation of Angiostrongylus costaricensis, nematode responsible for abdominal angiostrongyliasis to several species of terrestrial and freshwater molluscs and the differences observed in the interactions of trematodes with their intermediate hosts have induced us to study the concomitant infection of Biomphalaria glabrata with Schistosoma mansoni and A. costaricensis. Prior exposure of B. glabrata to A. costaricensis (with an interval of 48 hours), favored the development of S. mansoni, observing higher infection rate, increased release of cercariae and increased survival of molluscs, when compared to molluscs exposed only to S. mansoni. Prior exposure of B. glabrata to A. costaricensis and then to S. mansoni also enabled the development of A. costaricensis since in the ninth week of infection, higher amount of A. costaricensis L3 larvae was recovered (12 larvae / mollusc) while for molluscs exposed only to A. costaricensis, the number of larvae recovered was lower (8 larvae / mollusc). However, pre-exposure of B. glabrata to S. mansoni (with an interval of 24 hours), and subsequently exposure to A. costaricensis proved to be very harmful to B. glabrata, causing extensive mortality of molluscs, reduced pre-patent period to release cercariae and greater recovery of L3 A. costaricensis larvae.

The attraction exerted by Biomphalaria glabrata infected with Angiostrongylus costaricensis on Schistosoma mansoni miracidia of the BH strain was tested, using a glass apparatus composed by two circular chambers connected to a channel. One mollusk or a sample of a snail conditioning water (SCW) was placed in one of the chambers, randomly selected, and the remaining of the apparatus was filled with chlorine-free water. Ten miracidia were placed in the centre of the channel and their behaviour was observed for 15 minutes. Ten replicates were made for each treatment (snail or SCW), using different specimens of mollusks or different samples of SCW. Mollusks infected with A. costaricensis attracted significantly less S. mansoni miracidia than non-infected B. glabrata. In addition, miracidia were also significantly more attracted to SCW from mollusks infected with A. costaricensis.Keywords: Angiostrongylus costaricensis, Schistosoma mansoni, Biomphalaria glabrata, miracidia. Atração de miracídios de Schistosoma mansoni Sambon, 1907 por Biomphalaria glabrata (Say, 1818) infectada por Angiostrongylus costaricensis Morera and Céspedes, 1971Resumo Utilizando-se um artefato de vidro composto por duas câmaras unidas por um canal, testamos a atração miraxonal exercida por Biomphalaria glabrata infectada por Angiostrongylus costaricensis sobre miracídios de Schistosoma mansoni da linhagem BH. Um molusco ou uma amostra de sua água de condicionamento (SCW) foi colocado aleatoriamente em uma das câmaras, sendo o restante do artefato preenchido com água declorada. Dez miracídios foram colocados no centro do canal e seu comportamento foi observado por 15 minutos. Foram feitas dez replicações de cada experimento utilizando-se espécimes de moluscos ou de amostras de SCW diferentes. Moluscos infectados com A. costaricensis atraíram significativamente menos miracídios de S. mansoni que B. glabrata não infectada. Além disso, miracídios foram significativamente mais atraídos pela SCW de moluscos infectados com A. costaricensis.

Verificou-se a presença de conteúdos sobre o caracol-gigante-africano Achatina fulica nas coleções de Ciências e Biologia indicados pelo PNLD 2017/2018, quanto a presença de imagens e informações referentes à transmissão de doenças, e alertas sobre manejo e controle da população dessa espécie exótica invasora. Os resultados revelaram a ausência de qualquer menção sobre o molusco em 50 % das coleções de Ciências e em 30 % das coleções de Biologia, omissões/incorreções em conceitos e imagens, e algumas legendas equivocadas nos conteúdos encontrados. Concluiu-se que há necessidade de maiores cuidados na elaboração dessas coleções ao tratar de temas de interesse à saúde pública e ao meio ambiente, pois informações corretas contribuem na construção do conhecimento e na formação de atitudes que minimizam o risco de se contrair doenças além de evitar a frequente confusão entre o Achatina fulica e o molusco nativo Megalobulimus sp ameaçado de extinção.

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