Natural Leishmania (Viannia) infections of phlebotomines (Diptera: Psychodidae) indicate classical and alternative transmission cycles of American cutaneous leishmaniasis in the Guiana Shield, Brazil.

From 1996 to 1999 multi-trapping methods (Center of Diseases Control, CDC) light traps, light-baited Shannon traps, and aspiration on tree bases) were used to study the phlebotomine fauna of the "Serra do Navio" region of the Brazilian State of Amapá, which is part of the Guiana Shield. Fifty-three species were identified among 8,685 captured individuals. The following species, associated with the transmission of American cutaneous leishmaniasis in Amazonian Brazil, were captured: Nyssomyia umbratilis (3,388), Psychodopygus squamiventris maripaensis (995), Ny. anduzei (550), Trichophoromyia ubiquitalis (400), Ny. whitmani (291), Ps. paraensis (116), and Bichromomyia flaviscutellata (50). Flagellate infections were detected in 45 flies. Of the 19 parasites isolated in vitro, 15 were Leishmania (Viannia) guyanensis (13 in Ny. umbratilis, 1 in Ny. whitmani, 1 in Ny. anduzei) and three were L. (V.) naiffi (2 in Ps. s. maripaensis, 1 in Ny. anduzei). The results indicate the participation of three phlebotomine species in the transmission of L. (V.) guyanensis and two species in that of L. (V.) naiffi, and show that the same phlebotomine species is involved in the transmission of different Leishmania (Viannia) species in the Guianan/Amazon region. A review of the literature together with the results of the present study, and other published and unpublished results, indicate that eight phlebotomine species potentially participate in the transmission of Leishmania (Viannia) naiffi in Amazonia.

Comparative analysis of carbohydrate residues in the midgut of phlebotomines (Diptera: Psychodidae) from colony and field populations from Amazon, Brazil.

Leishmaniasis are worldwide diseases that occur in 98 countries including Brazil, transmitted by the bite of female phlebotomines during blood feeding. In Brazil it is known that some species of sand flies as Lutzomyia longipalpis sensun latum (vector of Leishmania infantum chagasi), Lutzomyia flaviscutellata (vector of Leishmania (Leishmania) amazonensis) and Lutzomyia antunesi [suspected vector of Leishmania (Viannia) lindenbergi] are incriminated of transmitting the parasite Leishmania for the vertebrate host. The phlebotomine-parasite is mediated by the attachment of the promastigote lipophosphoglycan (LPG) to the midgut epithelium. However, another mechanism that is LPG-independent and mediated by N-acetyl-galactosamine (GalNAc) seems to occur in some species of phlebotomines that are classified as permissive. The aim of this study was to characterize the carbohydrate residues that, probably, play a role in parasite attachment to the midgut of phlebotomine from colony and field populations from the Brazilian Amazonian region. We observed the presence of GalNAc, mannose, galactose and GlcNAc in all phlebotomine species. A binding assay between L. (L.) amazonensis and L. i.chagasi to the midguts of different species of phlebotomines was performed. The attachment of both Leishmania and vector species suggests the presence of GalNAc on the midgut surfaces. Thus, these results suggested that GalNAc is a possible binding sites of Leishmania in sand flies from the Brazilian Amazonian region.

Natural Leishmania (Viannia) spp. infections in phlebotomine sand flies (Diptera: Psychodidae) from the Brazilian Amazon region reveal new putative transmission cycles of American cutaneous leishmaniasis.

In Amazonian Brazil the etiological agents of American cutaneous leishmaniasis (ACL) belong to at least seven Leishmania species but little is known about the putative phlebotomine sand fly vectors in different biomes. In 2002-2003 a survey of the phlebotomine fauna was undertaken in the "Floresta Nacional do Tapajós", Belterra municipality, in the lower Amazon region, western Pará State, Brazil, where we recently confirmed the presence of a putative hybrid parasite, L. (V.) guyanensis × L. (V.) shawi shawi. Sand flies were collected from Centers for Disease Control (CDC) light traps, Shannon traps and by aspiration on tree bases. Females were dissected and attempts to isolate any flagellate infections were made by inoculating homogenized midguts into Difco B(45) medium. Isolates were characterized by monoclonal antibodies and isoenzyme electrophoresis. A total of 9,704 sand flies, belonging to 68 species or subspecies, were collected. Infections were found in the following sand flies: L. (V.) naiffi with Psychodopygus hirsutus hirsutus (1) and Ps. davisi (2); and L. (V.) shawi shawi with Nyssomyia whitmani (3) and Lutzomyia gomezi (1). These results provide strong evidence of new putative transmission cycles for L. (V.) naiffi and L. (V.) s. shawi.

Fauna flebotomínica da Serra dos Carajás, Estado do Pará, Brasil, e sua possível implicação na transmissão da leishmaniose tegumentar americana / Phlebotominae fauna in Serra dos Carajás, Pará State, Brazil, and its possible implications for the transmission of American tegumentar leishmaniasis

A Serra dos Carajás, localizada no sudeste do Estado do Pará, Brasil, representa uma rica floresta tropical, onde são encontradas espécies de Leishmania sp. de interesse médico, como L. (V.) braziliensis, L. (V.) lainsoni, L. (V.) shawi e L. (L.)amazonensis, cuja transmissão é feita pelos flebotomíneos: Psychodopygus complexus ou Ps. wellcomei, Lutzomyia ubiquitalis, Lu. whitmani e Lu. flaviscutellata. Considerando o incremento de imigrantes na região do projeto Carajás, realizou-se estudo para avaliar a fauna de flebotomíneos e sua possível participação na transmissão da leishmaniose tegumentar americana (LTA). Os flebotomíneos foram capturados: i) Parque Zoobotânico de Parauapebas, ii) Área deproteção ambiental e, iii) Floresta Nacional de Tapirapé-Aquiri, de dezembro/2005 a setembro/2007, usando-se dez armadilhas luminosas tipo "CDC" (18 h às 6 h) e duas tipo Shannon (18 h às 20 h), durante 172 dias de coleta. Foram capturados 22.095 flebotomíneos, 6.789 (31 por cento) machos e 15.306 (69 por cento) fêmeas, pertencentes a 69 espécies e três gêneros: Psychodopygus, Lutzomyia e Brumptomyia. Foram detectadas 19 (0,16 por cento) infecções naturais nas seguintes espécies: Ps. davisi (4), Ps. h. hirsutus (3), Lu. umbratilis (3), Lu. richardward (2), Lu. brachipyga (2), Lu. ubiquitalis (2), Lu. trinidadenses (1) e Lu. migonei (1). Embora não tenha sido encontrada infecção em Ps. wellcomei/complexus, principalvetor da L. (V.) braziliensis na região, esta espécie foi a mais prevalente (16 por cento), seguida de Ps. davisi (15,4 por cento), Ps. carrerai (4,2 por cento), Lu. shawi (3,9 por cento), Lu. brachipyga (2,5 por cento) e Lu. richardward (1,2 por cento). Estes resultados evidenciam a importância destes flebotomíneos como possíveis vetores da LTA na Serra dos Carajás.

Serra dos Carajás, located in the southeast of Pará State, Brazil, is a rich tropical forest where species of Leishmania sp. of medical interest are found, such as Leishmania (V.) braziliensis, L. (V.) lainsoni, L. (V.) shawi and L. (L.) amazonensis. They are transmitted by the following phlebotomi: Psychodopygus complexus or Ps. wellcomei, Lutzomyia ubiquitalis, Lu. whitmani and Lu. flaviscutellata. Considering the increase of immigrants in the region of the Carajás project, this study aimed to assess the Phlebotominae fauna and their possible participation in the transmission of American cutaneous leishmaniasis (ACL). The phlebotomi were captured from December 2005 to September 2007 at the following locations: i)Parauapebas Botanical Park; ii) an environmental protection area; and iii) Tapirapé-Aquiri National Forest. During the 172 days of collection, 10 CDC (18 h to 6 h) and 2 Shannon (18 h to 20 h) light traps were used. Of the 22,095 phlebotomi captured, 6,789 (31 percent) were male and 15,306 (69 percent) were female, and they belonged to 69 species and three genera,including Psychodopygus, Lutzomyia and Brumptomyia. A total of 19 (0.16 percent) natural infections of the following species were detected: Ps. davisi (4), Ps. h. hirsutus (3), Lu. umbratilis (3), Lu. richardward (2), Lu. brachipyga (2), Lu. ubiquitalis (2),Lu. trinidadensis (1) and Lu. migonei (1). Although no infection was found in Ps. wellcomei/complexus, the main vector of L. (V.) braziliensis in the region, this species was the most prevalent (16 percent), followed by Ps. davisi (15.4 percent), Ps. carrerai (4.2percent), Lu. shawi (3.9 percent), Lu. brachipyga (2.5 percent) and Lu. richardward (1.2 percent). These results show the importance of these phlebotomi as possible vectors of ACL in Serra dos Carajás.

Novas evidências sobre o valor diagnóstico da reação de imunofluorescência indireta e reação intradérmica de hipersensibilidade tardia na infecção humana por Leishmania (L) infantum chagasi na Amazônia, Brasil / New evidences on the diagnostic value of indirect immunofluorescence test and delayed hypersensitivity skin test in human infection by Leishmania (L ) infantum chagasi in the Amazon, Brazil

Estudo prospectivo realizado no período de maio/2006-setembro/2008, numa coorte de 1.099 indivíduos, ambos os sexos, com idades de 1 a 84 anos (média 24, 4 anos), residente em área endêmica de leishmaniose visceral americana (LVA) no Município de Cametá, Pará, Brasil, objetivando analisar a prevalência e a incidência da infecção humana por Leishmania (L.) infantum chagasi, assim como a dinâmica da evolução dos seus perfis clínico-imunológicos previamente definidos: 1. Infecção assintomática (IA); 2. Infecção sintomática (IS=LVA); 3. Infecção subclínica oligossintomática (ISO); 4. Infecção subclínica resistente (ISR); e 5. Infecção inicial indeterminada (III). O diagnóstico da infecção baseou-se no uso simultâneo da reação de imunofluorescência indireta (RIFI) e reação intradérmica de hipersensibilidade tardia. Um total de 304 casos da infecção foi diagnosticado no período do estudo (187 na prevalência e 117 na incidência), gerando prevalência acumulada de 27,6 por cento, cuja distribuição no âmbito dos perfis clínico-imunológicos foi da seguinte ordem: IA 51,6 por cento, III 22,4 por cento, ISR 20,1 por cento, ISO 4,3 por cento e, IS (=LVA) 1,6 por cento. Com base na dinâmica da infecção, o principal achado recaiu no perfil III, que teve papel fundamental na evolução da infecção, dirigindo-a ora para o pólo imunológico de resistência, perfis ISR (21 casos - 30,8 por cento) e IA (30 casos - 44,1 por cento), ora para o polo imunológico de susceptibilidade, perfil IS (um caso -1,5 por cento); além destes, 16 casos mantiveram o perfil III até o fim do estudo. Concluiu-se que esta abordagem diagnóstica pode ajudar no monitoramento da infecção na área endêmica, visando, principalmente, prevenir a morbidade da LVA, assim como reduzir o tempo e despesas com o tratamento.

This is a prospective study on a cohort of 1099 individuals of both genders, aged 1-84 years (mean 24.4 years), living in an endemic area of American visceral leishmaniasis (AVL) in the Municipality of Cametá, Brazil, from May 2006 to September 2008. It aimed to analyze the prevalence and incidence rates of human infection by Leishmania (L.) infantum chagasi, as well as the evolutional process of its previously defined clinical and immunological profiles: 1. Asymptomatic infection (AI);2. Symptomatic infection (SI = AVL); 3. Subclinical oligosymptomatic infection (SOI); 4. Subclinical resistant infection (SRI); and 5. Indeterminate initial infection (III). The diagnosis was based on the simultaneous use of indirect immunofluorescence assay (IFA) and delayed hypersensitivity skin test. A total of 304 cases of infection were diagnosed during the period studied(187 for prevalence and 117 for incidence), generating an accumulated prevalence rate of 27.6 percent. The distribution regarding their clinical and immunological profiles presented the following order: AI 51.6 percent; III 22.4 percent; SRI 20.1 percent; SOI4.3 percent; and SI (= AVL) 1.6 percent. Based on the dynamics of the infection, the main discovery was about the III profile, which had an instrumental role in its evolution, directing it either to the resistant immunological pole – SRI (21 cases - 30.8 percent) and AI (30 cases - 44.1 percent) profiles – or to the susceptible immunological pole – SI (1 case - 1.5 percent) profile. In addition, 16 cases remained within the III profile until the end of the study. It was concluded that this diagnostic approach can help monitor the infection in endemic areas, aiming mainly at preventing morbidity caused by AVL, and reducing the treatment time and expenses.

Epidemiologia de um caso de doença de Chagas na Ilha do Mosqueiro - Pará / Epidemiology of a case of Chagas' disease in the Mosqueiro Island - Para (Brazil)

Os autores apresentam os resultados do estudo epidemiológico de um caso autóctone da fase aguda da doença de Chagas na ilha do Mosqueiro. Estado do Pará, aproximadamente 75km da capital, Belém. O caso já havia sido objeto de uma publicaçäo anterior. Agora säo apresentadas informaçöes epidemiológicas. Nas proximidades da casa do paciente foram capturados em duas palmeiras de Inajá (Maximilian regia) e em uma da Mucajá (Acrocomia sclerocarpia) 114 triatomineos: Rhodnius pictipes, R. robustus, Panstrongylus lignarius, P. geniculatus e Microtriatoma trinidadensis, com tripanossomas em 31 deles. Na casa do paciente foram encontrados exemplares de Rhodnius pictipes, infectados com formas metacíclicas do Trypanosoma cruzi. Em 14 marsupiais, capturados na localidade, haviam 3 infectados com organismos semelhantes ao T. cruzi. A eletroforese dos isoenzimas nos tripanossomas isolados do paciente, de R. pictipes e de Didelphis marsupialis os classificou como zimodema 1. Os autores concluem que a doença de Chagas do paciente teve origem silvestre