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Visceral leishmaniasis in Brazil was initially associated with rural areas. However, due to several environmental modifications such as deforestation, urbanization and intense migratory processes, there has been an expansion of endemic areas, leading to urbanization of the disease, mainly in the central and northeastern regions of Brazil. In the municipality of Montes Claros, located in the north of the state of Minas Gerais, an epidemiological survey on VL was carried out. A canine serological inquiry was carried out in 2002 and an entomological survey, using luminous CDC traps, was performed from September 2002 to August 2003. Canine VL prevalence showed an average infection rate of approximately 5%. An estimated 16 species comprised the phlebotomine sand fly fauna, based on a total of 1043 specimens. The predominant species was Lutzomyia longipalpis with a rate of 74%, suggesting its participation in the transmission of VL in the municipality of Montes Claros.

A study of Lutzomyia longipalpis (Lutz and Neiva, 1912) (Diptera: Psychodidae), the primary vector of American visceral leishmaniasis (AVL), and the canine form of the disease, was carried out in Porteirinha. The city is situated in the northern part of the Brazilian State of Minas Gerais and is an endemic area of AVL. Systematic phlebotomine captures were performed in seven districts with previously reported cases of canine visceral leishmaniasis, during 2 years (January 2000--December 2001). A total of 2328 specimens of L. longipalpis were captured. The association between the local climate variables and the population density of L. longipalpis was evaluated and rainfall was determined to be a major factor, with increased populations during the rainy season (October--March). At the same time period, blood samples from every dog domiciled in the same seven districts, in total 14,077 animals, were analyzed for infection by viscerotropic Leishmania using indirect immunofluorescence assay (IFA). Accumulated incidence rates of canine VL per district varied from 3.40 to 14.34 for the 2-year period. A positive correlation between the population density of L. longipalpis and the canine cases of visceral leishmaniasis in Porteirinha was observed.

A study of the phlebotomine sand fly fauna was carried out in an endemic area of American visceral leishmaniasis (AVL) in the municipality of Porteirinha, in the Brazilian state of Minas Gerais. Captures were performed with CDC light traps in 7 districts, 5 days per month, during 2 consecutive years (January 2000 to December 2001). A total of 3240 sand flies were captured and identified. Sixteen species were found, among which 15 belonged to the genus Lutzomyia and one to the genus Brumptomyia. Lutzomyia longipalpis, a proven vector of AVL, was the predominant species (71.85%) throughout the time period. The interference of climatic factors (temperature, humidity, and rainfall) over the populational dynamics of the sand flies was determined. Statistical analysis of the data showed a significant correlation among the number of phlebotomine sand flies collected, rainfall, and humidity, whereas the effect of temperature was negligible, in that particular region. The amount of collected phlebotomine, the number of human cases, and the prevalence of canine AVL in the districts of Porteirinha are discussed.

An alkaline serineprotease, capable of hydrolyzing Nα-benzoyl- dl arginine p-nitroanilide, was secreted by Fusarium oxysporum var. lini grown in the presence of gelatin as the sole nitrogen and carbon source. The protease was purified 65-fold to electrophoretic homogenity from the culture supernatant in a three-step procedure comprising QSepharose chromatography, affinity chromatography, and FPLC on a MonoQ column. SDS-PAGE analysis of the purified protein indicated an estimated molecular mass of 41 kDa. The protease had optimum activity at a reaction temperature of 45°C and showed a rapid decrease of activity at 48°C. The optimum pH was around 8.0. Characterization of the protease showed that Ca2+ and Mg2+ cations increased the activity, which was not inhibited by EDTA or 1,10-phenanthroline. The enzyme activity on Nα-benzoyl- dl arginine p-nitroanilide was inhibited by 4-(2-aminoethyl)-benzenesulfonyl fluoride hydrochloride, p-aminobenzamidine dihydrochloride, aprotinin, 3–4 dichloroisocoumarin, and N-tosyl- l -lysine chloromethyl ketone. The enzyme is also inhibited by substrate concentrations higher than 2.5 × 10−4 M. The protease had a Michaelis-Menten constant of 0.16 mM and a Vmax of 0.60 μmol released product·min−1·mg−1 enzyme when assayed in a non-inhibiting substrate concentration. The activity on Nα-benzoyl- dl arginine p-nitroanilide was competitively inhibited by p-aminobenzamidine dihydrochoride. A Ki value of 0.04 mM was obtained.

Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Laboratório de Ecologia e Sistemática de Abelhas. Belo Horizonte, MG, Brazil Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Universidade Federal dos Vales do Jequitinhonha e Mucuri. Departamento de Ciências Biológicas. Diamantina, MG, Brasil Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Grupo de Estudos em Leishmanioses. Belo Horizonte, MG, Brasil Background: Sand fly collections were performed to study ecological aspects of the Phlebotominae fauna of the Xakriabá Indigenous Reserve, an area with endemic cutaneous leishmaniasis, located in the state of Minas Gerais, Brazil. Methods: The collections were performed in peridomicile areas and along trails previously selected for the study of wild and synanthropic Leishmania hosts. Differences in the distribution patterns of the sand fly species as well as in species richness and abundance between the different ecotopes were investigated during both rainy and dry seasons over the course of the study period. Results: A total of 8,046 sand flies belonging to 11 genera and 28 species were collected. Lutzomyia longipalpis and Nyssomyia intermédia were the most abundant species in peridomicile areas, whereas Martinsmyia minasensis and Lutzomyia cavernícola were the most abundant species among the different trail ecotopes. Conclusion: The different composition of the sand fly fauna observed in the peridomicile areas and in the trails during the study, reinforces the importance of sampled different areas in a phlebotomine fauna survey. The presence of Lutzomyia longipalpis and Ny. Intermedia most abundant in peridomicile can be important to Leishmania infantum and Leishmania braziliensis transmission in the Imbaúbas native village.

A morphometric survey examined adult specimens of Lutzomyia whitmani (Antunes & Coutinho) captured at 5 municipalities in southeastern and northeastern Brazil to compare the populations. The localities were Ilheus (Bahia), Martinho Campos (Minas Gerais), Corte de Pedra (Bahia), Baturite (Ceara), and Amaraji (Pernambuco): all are known foci of American cutaneous leishmaniasis. Fifteen males and 15 females from each population were analyzed morphometrically for 42 and 37 characters, respectively. Statistical data alone were insufficient to discriminate among the 5 populations. Further analysis generated phenograms that indicated there were 2 spatial clusters: the 1st was composed of specimens from Ilheus (Bahia) and Baturite (Ceara) and the 2nd of specimens from Martinho Campos (Minas Gerais), Corte de Pedra (Bahia), and Amaraji (Pernambuco). Although insufficient to define the taxonomic status of the populations studied, the results delineated the existence of biogeographical structuring within L. whitmani. Complementary studies on the susceptibility to Leishmania braziliensis infection in the 5 populations are in progress to clarify the relationship between the 2 biogeographical clusters and American cutaneous leishmaniasis transmission in those Brazilian regions.

A new species of Nemapalpus Macquart collected in caverns in the state of Minas Gerais, southeastern Brazil, is described and named Nemapalpus spinosus sp. nov. A current list of the western hemisphere species of the genus is provided.