Flexible prey handling, preference and a novel capture technique in invasive, sub-adult Chinese mitten crabs

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The attached file is the published version of the article

Impactos socioeconômicos de uma doença emergente Socioeconomic impacts of an emerging disease

Em 1995, ocorreu uma praga de lesmas identificadas como Sarasinula linguaeformis (Semper, 1885), que prejudicou as lavouras situadas entre os municípios de Nova Itaberaba e Planalto Alegre, no oeste do estado de Santa Catarina, Brasil. Neste artigo analisamos os impactos socioeconômicos provocados pela ocorrência desta praga, que sinalizou a possibilidade, posteriormente verificada, da emergência de casos de angiostrongilíase abdominal. Os dados foram coletados através de observação do estudo soroepidemiológico realizado na região durante o período de agosto de 2000 a agosto de 2001 pela equipe de pesquisa da Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), entrevistas com técnicos da Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina S.A. (Epagri-SC) e com cinquenta famílias locais. Para avaliar esses impactos, elaboramos algumas categorias de análise, como: prejuízo econômico; medidas preventivas e mudança de hábitos; estigma e preconceito, que surgiram à luz das narrativas dos sujeitos entrevistados. Ficou evidente a necessidade de se procederem a estudos sobre os aspectos sociológicos dos problemas epidemiológicos, além dos estritamente médico-sanitários.<br>In 1955 a population explosion of the slug Sarasinula linguaeformis (Semper, 1885) damaged crop plantations in the municipalities of Nova Itaberaba and Planalto Alegre, western of Santa Catarina State, Brazil. In this article we analyze the socioeconomic impacts caused by the emergence of this plague, which raised the suspicion, eventually confirmed, of the occurrence of human cases of abdominal angyostrongiliasis. The data were collected through the observation of a serological study during the period of August 2000 to August 2001 by a research team from the Catholic University of Rio Grande do Sul (PUCRS) together with field technicians from the Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina S.A. (Epagri-SC), and with the members of 50 local families. In order to analyze these impacts, we elaborated several analytical categories as economic losses; preventive measures, habit change and social prejudice, that emerged from the narratives of the residents interviewed. It became evident the need for sociological analyses of epidemiological problems, in addition to strictly medico-sanitary considerations

Distribution of Angiostrongylus vasorum and its gastropod intermediate hosts along the rural–urban gradient in two cities in the United Kingdom, using real time PCR

BACKGROUND: Angiostrongylus vasorum is a highly pathogenic metastrongylid nematode affecting dogs, which uses gastropod molluscs as intermediate hosts. The geographical distribution of the parasite appears to be heterogeneous or patchy and understanding of the factors underlying this heterogeneity is limited. In this study, we compared the species of gastropod present and the prevalence of A. vasorum along a rural–urban gradient in two cities in the south-west United Kingdom. METHODS: The study was conducted in Swansea in south Wales (a known endemic hotspot for A. vasorum) and Bristol in south-west England (where reported cases are rare). In each location, slugs were sampled from nine sites across three broad habitat types (urban, suburban and rural). A total of 180 slugs were collected in Swansea in autumn 2012 and 338 in Bristol in summer 2014. A 10 mg sample of foot tissue was tested for the presence of A. vasorum by amplification of the second internal transcribed spacer (ITS-2) using a previously validated real-time PCR assay. RESULTS: There was a significant difference in the prevalence of A. vasorum in slugs between cities: 29.4 % in Swansea and 0.3 % in Bristol. In Swansea, prevalence was higher in suburban than in rural and urban areas. Comparing the sampled slug fauna, Arion rufus was found in greater numbers in Swansea than Bristol, and was commonly infected (prevalence 41 %). This, alongside the timing of slug collections in summer rather than autumn, could explain low infection prevalence in the Bristol sample. In the absence of Ar. rufus as a preferred host for A. vasorum, Ar. flagellus and Limacus maculatus appear to act as versatile hosts that are present in suburban and urban areas in Swansea (prevalence in Ar. flagellus 33 %; in L. maculatus 44 %) and in Bristol (prevalence in Ar. flagellus 0.9 %). These slug species might provide A. vasorum with an alternative vehicle to reach the final host, when the main host Ar. rufus is scarce or absent. CONCLUSION: We conclude that the composition of the slug fauna varies spatially, and that this could help explain patchiness in the prevalence of A. vasorum. A suburban peak was found in the prevalence of infection in intermediate hosts, perhaps explained by a higher density of competent intermediate and/or definitive hosts