OBJECTIVE:Investigate breeding sites with host snails and autochthonous human cases of schistosomiasis. METHODS:Between July 2010 and September 2012 were performed: (1) malacological survey searching for breeding sites, collection and identifi cation of Biomphalaria snails positive for Schistosoma mansoni in Recife, PE, Northeastern Brazil; (2) prevalence survey in 2,718 schoolchildren aged from seven to 14 years old to identify cases of schistosomiasis, clinical examination and ultrasound in positive cases of S. mansoni. The autochthony of the cases was investigated and the case were clinically evaluated. The cases and breeding sites were georeferenced and spatially described. RESULTS:The results identifi ed 30 breeding with B. straminea, four of which were potential foci of transmission, as molecular testing identifi ed snails with S. mansoni DNA. There were 14 children diagnosed with schistosomiasis, of which fi ve were considered to be autochthonous cases of the disease. CONCLUSIONS:Urgent measures are required in order to avoid schistosomiasis becoming endemic to Recife, as has happened in other coastal areas of the state of Pernambuco.

Abstract. In 2012 a malacological survey of the breeding sites of Biomphalaria glabrata and B. straminea, the two intermediate host snails of Schistosoma mansoni, was carried out on Itamaraca Island in Pernambuco, Brazil. This study has now been extended by studying the competition between the two species. Snails were collected and dissected to identify the species and tests were performed to verify S. mansoni infection. Student's t test was used to compare the proportion between the two species and their breeding sites and a parasitological survey was conducted among local residents, using the Kato-Katz method. The spatial distribution of the two snail species was determined using TerraView, while a snail density map was constructed by Kernel estimate. The survey identified two breeding sites for B. glabrata with 17 specimens and 19 breeding sites for B. straminea with 459 snails, all of them negative for S. mansoni infection. The statistical analysis revealed that the proportion of the numbers of specimens and breeding sites of B. straminea (37.84 ± 9.01) were significantly greater than those of B. glabrata (8.50 ± 6.50). Parasitological examinations from 41 residents diagnosed two cases of schistosomiasis with parasite loads of 60 and 84 eggs per 1 g of stool, respectively. This indiction of a competitive process between the two snail species requires monitoring of schistosomiasis in the resident and travelling human populations occupying this environment, which could potentially result in social and economic changes on the island risking its attraction as a centre for eco-tourism.

Realizou-se um inquérito malacológico em criadouros, permanentes e temporários, no bairro de Piedade, Jaboatão dos Guararapes, Pernambuco, entre novembro de 2006 e novembro de 2007 com o objetivo de conhecer a fauna malacológica dessa localidade, bem como o potencial de transmissão da esquistossomose mansoni. Além de Biomphalaria glabrata (Say, 1818), foram coletados moluscos Drepanotrema cimex (Moricand, 1837), Pomacea sp e Melanoides tuberculatus (Muller, 1774). Do total de Biomphalaria glabrata coletado, 1.490 exemplares encontraram-se vivos, sendo que 74 (5%) estavam positivos para Schistosoma mansoni. O maior número de moluscos capturados e todos aqueles positivos para Schistosoma mansoni foram coletados na estação anual das chuvas. Foi observada também a presença de outras larvas de trematódeos infectando os moluscos Biomphalaria glabrata. Pertencentes às famílias Strigeidae e Diplostomatidae, apresentam, a primeira vista, morfologia que pode levar a confusão com as cercárias do Schistosoma mansoni, tornando-se indispensável seu conhecimento para o diagnóstico diferencial do agente causador da esquistossomose.

ABSTRACT. Ecological aspects and malacological survey to identification of transmission riskglabrata collected, 44 specimens were positive for Schistosoma mansoni Sambon, 1907 cercariae and 91 specimens were positive for other trematode larvae. One Pomacea sp. specimen was positive for trematode larvae. These data, spatially georeferenced, will be used for determination of risk' sites for schistosomiasis transmission at Carne de Vaca beach and furthermore, they will be used for computational simulations to determine the expansion process of schistosomiasis in state of Pernambuco.

INTRODUCTION: The prevalence and intensity of geohelminth infections and schistosomiasis remain high in the rural areas of Zona da Mata, Pernambuco (ZMP), Brazil, where these parasites still represent a significant public health problem. The present study aimed to spatially assess the occurrences of schistosomiasis and geohelminthiasis in the ZMP. METHODS: The ZMP has a population of 1,132,544 inhabitants, formed by 43 municipalities. An ecological study was conducted, using secondary data relating to positive human cases and parasite loads of schistosomiasis and positive human cases of geohelminthiasis that were worked up in Excel 2007. We used the coordinates of the municipal headquarters to represent the cities which served as the unit of analysis of this study. The Kernel estimator was used to spatially analyze the data and identify distribution patterns and case densities, with analysis done in ArcGIS software. RESULTS: Spatial analysis from the Kernel intensity estimator made it possible to construct density maps showing that the northern ZMP was the region with the greatest number of children infected with parasites and the populations most intensely infected by Schistosoma mansoni. In relation to geohelminths, there was higher spatial distribution of cases of Ascaris lumbricoides and Trichuris trichiura in the southern ZMP, and greater occurrence of hookworms in the northern/central ZMP. CONCLUSIONS: Despite several surveys and studies showing occurrences of schistosomiasis and geohelminthiasis in the ZMP, no preventive measures that are known to have been effective in decreasing these health hazards have yet been implemented in the endemic area.