Entomological characterization and natural infection of anophelines in an area of the Atlantic Forest with autochthonous malaria cases in mountainous region of Espírito Santo State, Brazil

Autochthonous malaria cases in the state of Espírito Santo, Brazil, are distributed in mountainous regions surrounded by the Atlantic Forest. While some aspects of this disease are unclear, detection of possible vector species can help to elucidate epidemiological uncertainties. Entomological and natural infection studies were carried out using anophelines (Diptera: Culicidae) captured in the municipality of Santa Tereza, ES. Monthly captures were made from March 2004 to February 2006. CDC-CO2 traps were used from dusk (6:00 P.M.) to dawn (6:00 A.M.) to capture anophelines in the following habitats: near the houses, in open areas (at ground level) and inside, and at the margins of the forest (canopy and ground level). Shannon light traps were also used at the same locations of the CDC-CO2 traps. A total of 2,290 anophelines within 10 species were captured. The relative frequency of Anopheles (Kerteszia) cruzii Dyar & Knab / A.(K.) homunculus Komp was the highest, with the majority captured in CDC-CO2 traps installed in the forest canopy. The main species captured in Shannon traps was A.(Nyssorhynchus) strodei Root. The largest number of anophelines was captured from July to September and from 6:00 P.M. to 10:00 P.M. Anopheles (K.) cruzii is the probable vector for malaria transmission inside or near the Atlantic Forest fragments, but the role of other species cannot be ignored, as 53% of the sampled anophelines belonged to the subgenus Nyssorhynchus. The natural infection of A. cruzii, A. parvus (Chagas) and A. galvaoi Causey, Deane & Deane by Plasmodium vivax detected by PCR from DNA extracted from their thoraxes supports this view. No Espírito Santo, os casos de malária autóctone estão distribuídos na região serrana próximo aos fragmentos de Mata Atlântica. Uma vez que alguns aspectos da doença são obscuros, a detecção das possíveis espécies de vetores pode auxiliar na elucidação de incertezas epidemiológicas. Estudos entomológicos e de infecção natural foram realizados com anofelinos (Diptera: Culicidae) capturados no município de Santa Tereza, ES. Capturas mensais foram realizadas de março de 2004 a fevereiro de 2006. Armadilhas CDC-CO2 foram utilizadas do crepúsculo (18:00h) ao amanhecer (6:00h), para capturar anofelinos nos seguintes habitats: próximo ao domicílio e área aberta (solo), margem e interior da mata (solo e copa). Armadilhas Shannon também foram utilizadas nos mesmos locais que as de CDC-CO2. Capturou-se o total de 2.290 anofelinos distri