Prevalence and distribution of angiostrongylus cantonensis (nematoda, angiostrongylidae) in achatina fulica (mollusca, gastropoda) in baixada santista, São Paulo, Brazil

ABSTRACT INTRODUCTION Angiostrongylus cantonensis is 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.

Brazilian Angiostrongylus cantonensis haplotypes, ac8 and ac9, have two different biological and morphological profiles

Angiostrongylus cantonensis is the etiologic agent of eosinophilic meningoencephalitis in humans. Cases have been recorded in many parts of the world, including Brazil. The aim of this study was to compare the differences in the biology and morphology of two different Brazilian haplotypes of A. : ac8 and ac9. A significantly larger number of L1 larvae eliminated in the faeces of rodents at the beginning of the patent period was observed for ac9 haplotype and compared to the total of L1 larvae eliminated, there was a significant difference between the two haplotypes. The ac9 haplotype showed a significant difference in the proportion of female and male specimens (0.6:1), but the same was not observed for ac8 (1.2:1). The morphometric analysis showed that male and female specimens isolated from ac8 haplotype were significantly larger with respect to body length, oesophagus length, spicule length (male) and distance from the anus to the rear end (female) compared to specimens from ac9. The morphological analysis by light microscopy showed little variation in the level of bifurcations at the lateral rays in the right lobe of the copulatory bursa between the two haplotypes. The biological, morphological and morphometric variations observed between the two haplotypes agree with the observed variation at the molecular level using the cytochrome oxidase subunit I marker and reinforce the possible influence of geographical isolation on the development of these haplotypes.

Estudo filogenético, biológico e morfológico de isolados de Angiostrongylus cantonensis provenientes de diferentes áreas geográficas do Brasil / Phylogenetic, biological and morphological analysis of angiostrongylus cantonensis isolates from different geographical areas of Brazil

Angiostrongylus cantonensis é responsável por causar meningoencefaliteeosinofílica em humanos e casos já foram registrados em diversas partes do mundoincluindo o Brasil (ES, PE e SP). Nesse estudo, relatamos a variabilidade genéticaentre isolados de A. cantonensis do Brasil utilizando sequências do genemitocondrial COI. Foram identificados três haplótipos brasileiros de A. cantonensis,baseados em oito haplótipos conhecidos (ac1-ac8). O haplótipo brasileiro ac5 ficouagrupado com isolados do Japão e o haplótipo brasileiro ac8 (isolados do RJ, SP,PA e PE) formaram um clado distinto. Foi relatado um novo haplótipo brasileiro,haplótipo ac9, o qual se encontra intimamente relacionado com os haplótipos daChina (ac6) e do Japão (ac7). Dois isolados brasileiros de A. cantonensis, Olinda eCaju (haplótipos ac8 e ac9, respectivamente) relatados no presente estudo, tiveramsua biologia e morfologia caracterizadas após infecção experimental. Foi observadadiferença significativa com maior carga parasitária recuperada nos isolados de Cajue um número significativamente maior de larvas L1 eliminadas nas fezes no início doperíodo patente. Entretanto, quando comparado o total de larvas eliminadas não foiverificada diferença significativa entre os dois isolados...

Angiostrongylus cantonensis is responsible for causing eosinophilicmeningoencephalitis in humans and cases have been recorded in various parts ofthe world including Brazil (ES, PE and SP). In this study, we report the geneticvariability among Brazilian isolates of A. cantonensis using sequences of themitochondrial COI gene. We identified three Brazilian haplotypes of A. cantonensis,based on eight known haplotypes (ac1-ac8). The Brazilian haplotype ac5, wasclustered with isolates from Japan and the Brazilian haplotype ac8 (isolates from RJ,SP, PA and PE) formed a distinct clade. It was reported a new Brazilian haplotype,haplotype ac9, which is closely related to haplotype from China (ac6) and Japan(ac7). Two Brazilian isolates of A. cantonensis, Olinda and Caju (haplotypes ac8 andac9, respectively) reported in this study, had their biology and morphologycharacterized after experimental infection. Significant differences were observed withhigher parasite load recovered in the isolates from Caju and a significantly greaternumber of L1 larvae eliminated in the feces at the beginning of the patent period.However, when compared to the total larvae eliminated there was no significantdifference between the two isolates. The isolates from Caju showed significantdifference in the proportion of female and male specimens (0,64:1), but it was notobserved for isolates from Olinda (1,16:1)...