Janduhy Pereira dos Santos

Monitoramento da suscetibilidade de populações de Triatoma sordida Stål, 1859 (Hemiptera: Reduviidae) ao inseticida deltametrina, na região Centro-Oeste do Brasil

INTRODUCAO: Populacoes de Triatoma sordida Stal, 1859 foram investigadas quanto a suscetibilidade a deltametrina. METODOS: Analise por meio de bioensaios por aplicacao topica em 11 populacoes de T. sordida procedentes dos Estados de Goias, Mato Grosso e Mato Grosso do Sul. RESULTADOS: As estimativas de DL50 e RR50 demonstraram elevados niveis de suscetibilidade (DL50 < 1 e RR50 < 2). Entretanto, as analises do coeficiente angular da curva dose resposta revelaram que as populacoes de triatomineos dos municipios de Firminopolis/GO, Posse/GO, Poxoreu/MT, Douradina/MS e Aparecida do Taboado/MS apresentam maiores probabilidades de evolucao de resistencia, portanto, mais propicias a tolerar o tratamento com deltametrina. CONCLUSOES: Detectaram-se pequenas alteracoes de suscetibilidade e baixos niveis de resistencia, porem as alteracoes temporais de suscetibilidade deverao ser continuamente monitoradas, a fim de nortear adequadamente as acoes de controle dos vetores da DC.

Uso e ocupação do solo e a disseminação da hantavirose na região de São Sebastião, Distrito Federal: 2004 - 2008

INTRODUCTION Hantavirosis has worldwide distribution and is an important public health problem. The epidemiology of hantavirosis in Brazil shows that the number of cases notified and the number of variants discovered in several states and the Federal District have been increasing year by year. Within this context, the main objective of this study was to examine land use and occupation in relation to the spread of hantavirosis in the Federal District, between 2004 and 2008. METHODS To carry out this investigation, epidemiological and land use data were used to drafting tables and cartograms in order to detail the special spread of hantavirosis in this area. RESULTS Out of the 40 likely infection sites plotted on the coverage and land use map, 19 (47%) were in pasture areas, 10 (25%) in urban areas (periurban), 6 (15%) in areas used for agriculture and 5 (12%) in savanna areas. CONCLUSIONS It can thus be seen that agricultural activities and urban expansion towards the savanna areas have favored the spread of hantavirosis in the Federal District and especially in São Sebastião.

Amblyomma ticks and future climate: Range contraction due to climate warming

Ticks of the Amblyomma cajennense species complex are important vectors of spotted fever in Latin America. Environmental conditions determine the geographic distribution of ticks, such that climate change could influence the distribution of tick-borne diseases. This study aimed to analyze the potential geographic distribution of A. cajennense complex ticks in a Brazil region under present-day and future climate models, assuming dispersal limitations and non-evolutionary adaptation of these tick populations to climate warming. Records of A. cajennense sensu stricto (s.s.) and Amblyomma sculptum were analyzed. Niche models were calibrated using Maxent considering climate variables for 1950-2000 and projecting models to conditions anticipated for 2050 and 2070 under two models of future climate (CCSM4 and HadGEM2-AO). Broad suitable areas for A. cajennense s.s. and A. sculptum were found in present-day climate models, but suitability was reduced when models were projected to future conditions. Our exploration of future climates showed that broad areas had novel climates not existing currently in the study region, including novel extremely high temperatures. Indeed, predicted suitability in these novel conditions would lead to biologically unrealistic results and therefore incorrect forecasts of future tick-distribution. Previous studies anticipating expansions of vectors populations due to climate change should be considered with caution as they assume that model extrapolation anticipates that species would evolve rapidly for adaptation to novel climatic conditions.