Nanci Akemi Missawa

Evidência de transmissão de leishmaniose visceral por Lutzomyia cruzi no município de Jaciara, Estado de Mato Grosso, Brasil

INTRODUCTION: The municipality of Jaciara was classified in 2003 as a transmission area for visceral leishmaniasis in outbreak situations. This study aimed to establish evidence of transmission of Leishmania (Leishmania) infantum chagasi by Lutzomyia cruzi in the municipality of Jaciara, State of Mato Grosso, Brazil. METHODS: This municipality is located 127 km from the state capital (Cuiaba) and is an important center for ecotourism practitioners. Females of Lutzomyia cruzi, captured using CDC traps, were dissected to confirm the species and stored at -20oC in pools of 10 individuals for DNA extraction, generic PCR, specific RFLP and electrophoresis on polyacrylamide gel. RESULTS: The entomological survey showed abundant occurrence of Lutzomyia cruzi and absence of Lutzomyia longipalpis (the main vector for Leishmania (Leishmania) infantum chagasi). One of the three samples showed a characteristic DNA band from Leishmania (120 bp) in generic PCR. To confirm the Leishmania species via RFLP, positive controls for Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis and Leishmania (Leishmania) infantum chagasi digested with restriction enzyme HaeIII were used. A pattern of bands similar to Leishmania (Leishmania) infantum chagasi was found in one sample, thus confirming the detection of natural infection with Leishmania (Leishmania) infantum chagasi in Lutzomyia cruzi. CONCLUSIONS: The occurrences of positive cases in humans and dogs, the presence of Lutzomyia cruzi and the absence of Lutzomyia longipalpis together with the detection of natural infection with Leishmania (Leishmania) infantum chagasi, indicate that Lutzomyia cruzi participates in visceral leishmaniasis transmission in Jaciara, State of Mato Grosso, Brazil.

Distribuição espacial de Lutzomyia longipalpis (Lutz & Neiva, 1912) e Lutzomyia cruzi (Mangabeira, 1938) no estado de Mato Grosso

Visceral leishmaniasis is currently considered an emergent and reemergent disease, in agricultural and urban zones, both in domestic and peridomestic areas. The objective of this work was to verify the spatial distribution of Lutzomyia longipalpis and Lutzomyia cruzi in Mato Grosso State. Data from 1996 to 2004 was collected by the Entomology Laboratory, whose captures were carried with a CDC light trap. Sixty-eight of the 139 cities in the state have been studied. Lutzomyia longipalpis and Lutzomyia cruzi occurred in 23 and 22 cities, respectively. The results demonstrate the extensive occurrence of Lutzomyia longipalpis in areas with different vegetation types: savanna, transition and Amazon forest. Lutzomyia cruzi occurred mainly in cities with areas of marshland and savanna. Verification of the distribution of the vector populations in the state and their preferential vegetation type, provides an indication of vulnerable and/or receptive areas for disease transmission.

Preferência alimentar de Lutzomyia longipalpis (Lutz & Neiva, 1912) em área de transmissão de leishmaniose visceral em Mato Grosso

Studies on the feeding habits and intestinal content of sandflies make it possible to identify hosts, thereby indicating potential reservoirs for Leishmania. The present study had the aim of determining the feeding preferences of Lutzomyia longipalpis and its relationship with the transmission of visceral leishmaniasis. Specimens were caught every month in a transmission area of visceral leishmaniasis, in the municipality of Varzea Grande, State of Mato Grosso, from January 2004 to June 2006, using CDC light traps. 2,376 females of Lutzomyia longipalpis were caught, of which 104 (4.4%) were engorged. Among these, 32 (30.8%) were caught inside homes and 72 (69.2%) in areas surrounding homes. From the precipitin reaction, it was observed that Lutzomyia longipalpis females fed preferentially on birds (30.8%) and rodents (21.2%), but they were also found to have fed on blood from humans, opossums, oxen, horses and dogs, thus demonstrating the opportunist nature of this species.

Visceral leishmaniasis in the municipality of Várzea Grande, State of Mato Grosso, between 1998 and 2007

This study aimed to describe the epidemiology and spread of visceral leishmaniasis in the municipality of Várzea Grande, State of Mato Grosso, Brazil, between 1998 and 2007. Forty-eight human cases were reported, with an incidence rate of up to 11.7 per 100,000 inhabitants, particularly among children and adolescents of both sexes, with marked geographical spread of the disease in the municipality.

List of species in the genus Lutzomyia, França, 1924 (Psychodidae, Phlebotominae) from the State of Mato Grosso

This work had the objective of listing the sand fly species that occur in the State of Mato Grosso, Brazil. Data relating to entomological surveys conducted between 1996 and 2004 were obtained from the National Health Foundation and the State Health Department, and this was supplemented with information from research carried out in the state and from the specialized literature. There were records of 106 sand fly species belonging to the genus Lutzomyia. This is a rich and diversified fauna, with some species restricted to forested areas and others recorded throughout the state, independent of the vegetation type, and in areas modified by human action, with predominance of Lutzomyia whitmani.

Distribuição geográfica de Lutzomyia (Nyssomyia) whitmani (Antunes & Coutinho, 1939) no Estado de Mato Grosso

In the State of Mato Grosso, 100% of the municipalities have records of autochthonous cases of American cutaneous leishmaniasis. The present study had the aim of investigating the geographical distribution of the Lutzomyia whitmani in the state. Mato Grosso has three distinct ecosystems: the savannah, the marshland and the area of the Amazon domain. Data on occurrences of Lutzomyia whitmani were obtained from reports on entomological surveys carried out by the Entomology Group of the National Health Foundation between 1996 and 2000 and by the Entomology Laboratory of the Mato Grosso State Health Department between 2001 and 2006. Entomological surveys were performed in 83 (59.7%) of the 139 municipalities of Mato Grosso. Lutzomyia whitmani was caught in 70 (84.3%) municipalities, with widespread distribution in all types of vegetation.

Lutzomyia longipalpis naturally infected by Leishmania (L.) chagasi in Várzea Grande, Mato Grosso State, Brazil, an area of intense transmission of visceral leishmaniasis

The American visceral leishmaniasis (AVL) is caused by parasites belonging to the genus Leishmania (Trypanosomatidae) and is transmitted to humans through the bite of certain species of infected phlebotomine sand flies. In this study, we investigated the natural infection ratio of Lutzomyia longipalpis, the main vector species of AVL in Brazil, in Várzea Grande, Mato Grosso State. Between July 2004 and June 2006, phlebotomine sand flies were captured in peridomestic areas using CDC light-traps. Four hundred and twenty (420) specimens of Lu. longipalpis were captured. 42 pools, containing 10 specimens of Lu. longipalpis each, were used for genomic DNA extraction and PCR (polymerase chain reaction) amplification. Leishmania spp. DNA was detected in three out of the 42 pools tested, resulting in a minimal infection ratio of 0.71%. Restriction fragment length polymorphism (RFLP) analysis indicated that Leishmania (L.) chagasi was the infective agent in the positive pools.

Fauna flebotomínica (Diptera: Psychodidae) em aldeias indígenas do Estado de Mato Grosso

This study was conducted in 25 indigenous villages in 13 municipalities of the State of Mato Grosso. 4,424 specimens of 37 species of the genus Lutzomyia and one species of the genus Brumptomyia were identified. Vectors for American tegumentary leishmaniasis and visceral leishmaniasis were abundantly captured, and these represented 28.7% (Lutzomyia whitmani) and 23.6% (Lutzomyia longipalpis), respectively.

Descrição de fauna anofélica em área endêmica de malária no Município de Colniza, Estado de Mato Grosso, Brasil

Objective: this study describes the fauna and the behavior of Anopheles species in order to understand the link in the entomological malaria transmission in the Municipality of Colniza, State of Mato Grosso. Methods: data were collected from the Information System of Epidemiological Surveillance of Malaria (Sivep-malaria), and from entomological reports of the city in March, May, July and September 2008. Results: presence of Anopheles darlingi, An. benarrochi, An. mediopunctatus, An. triannulatus and An. nuneztovari was observed; An. darlingi (97.5%) was the predominant species, captured in all months covered by the study but with high density in May, with increased activity in the evening and at home. Conclusion: in five present species collected, the main vector species of malaria, An.darlingi, was predominant in peridomiciliar area, with high density in May; such information allow to direct actions of control considering aspects related to the behavior of the vectors.