In this study, we identified the phlebotomine sandfly vectors involved in the transmission of American Cutaneous Leishmaniasis (ACL) in Assis Brasil, Acre, Brazil, which is located on the Brazil-Peru-Bolivia frontier. The genotyping of Leishmania in phlebotomines was performed using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism. A total of 6,850 sandflies comprising 67 species were captured by using CDC light traps in rural areas of the municipality. Three sandfly species were found in the state of Acre for the first time: Lutzomyia georgii, Lu. complexa and Lu. evangelistai. The predominant species was Lu. auraensis/Lu. ruifreitasi and Lu. davisi (total 59.27%). 32 of 368 pools were positive for the presence of Leishmania DNA (16 pools corresponding to Lu. davisi, and 16 corresponding to Lu. auraensis/Lu. ruifreitasi), with a minimal infection prevalence of 1.85% in Lu. davisi and 2.05% in Lu. auraensis/Lu. ruifreitasi. The Leishmania species found showed maximum identity with L. (Viannia) guyanensis and L. (V.) braziliensis in both phlebotomine species. Based on these results and similar scenarios previously described along the Brazil/Peru/Bolivia tri-border, the studied area must take into consideration the possibility of Lu. davisi and Lu. auraensis/Lu. ruifreitasi as probable vectors of ACL in this municipality.

51 years old (26.9% urban and 61.5% rural). High prevalence rates were observed in retired people (27.1% urban area), housewives and farmer (41.6% and 25%, respectively, in rural area). The main clinical symptoms were joint pains and sensation of leg coldness. Only Cerqueirellum argentiscutum (Simuliidae) transmits M. ozzardi in this municipality (PIR = 5.6% urban and 7.1% rural). M. ozzardi is a widely distributed parasitic disease in Coari. Thus, temporary residency in the region of people from other localities involved with the local gas exploitation might be a contributing factor in spreading the disease.]]>

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This study was undertaken to investigate the prevalence of Mansonella ozzardi infection and to estimate the parasitic infection rate (PIR) The filaria Mansonella ozzardi, one of the aetiological agents of mansonelliasis, is found on the American continent, as well as countries in the Caribbean. In South America, it has been reported in Panama, Colombia, Venezuela, Guyana, Suriname, Brazil, Argentina and Peru (Kozek et al. 1982). M. ozzardi is transmitted by Diptera insects of the families Ceratopogonidae in the Caribbean islands and Ceratopogonidae and Simuliidae in Central and South America (Shelley & Coscarón 2001).The pathogenicity of this filaria is not well defined. Several infected individuals show no symptoms; however, clinical manifestations that decrease the quality of life such as moderate fever, coldness in the legs, joint pains and headaches have been attributed to M. ozzardi infection (Batista et al. 1960b). Recently, the presence of ocular lesions has been reported as possibly associated with M. ozzardi infection (Branco et al. 1998, Cohen et al. 2008.The microfilaria M. ozzardi was detected in Brazil in the 1940s and 1950s (Deane 1949, Deane et al. 1954, Lacerda & Rachou 1956) and was described as a potentially extensive problem (Moraes 1958). Recently, some studies have shown that this filaria is still found with high prevalence (Medeiros et al. 2007(Medeiros et al. , 2008 and that simuliids are incriminated in the parasite's transmission in Brazil (Cerqueira 1959, Shelley & Shelley 1976, Shelley et al. 1980). Due to the absence of data and the importance of M. ozzardi for Amazonian populations, studies are still necessary to understand the geographical distribution of the cases, as well as the individual and cultural characteristics of the population in endemic areas that make them prone to infection. Indeed, eye lesions possibly associated with M. ozzardi have already been reported in the municipality of Pauini (Branco et al. 1998) and high prevalence rates were found in indigenous communities (Medeiros et al. 2007). Thus, our goal was to obtain data on human infection by M. ozzardi through comparison of prevalence rates between genders, as well as to examine the relationships between M. ozzardi infection and age and professional occupation. We also sought to identify the simuliid species involved in the transmission of M. ozzardi and to estimate the Parasitic Infection Rate (PIR) of the vectors. MATERIALs AND METHODsStudy area and population -This study was performed in the Purus and Pauini riverine communities in the municipality of Pauini (07º421'S 67º01'W), Amazonas (AM) (Fig. 1). The municipality of Pauini is located in southwest AM, about 900 km from Manaus. It has 17,092 inhabitants, with 6,970 in the urban zone and 10,122 in rural areas (IBGE 2000). The region is covered by native primary forest and presents long flood areas, accessible only by plane or boat. The rainy season is usually from November-March, with average annual temperatures between 24-26ºC, and a relative humidity bet...

BACKGROUND The state of Rondônia (RO) is a hot spot for human cases of cutaneous leishmaniasis. Many sandfly species in RO are putative vectors of leishmaniasis. OBJECTIVES This study examines the diversity patterns and the presence of Leishmania DNA and blood meal sources of sandflies in RO. METHODS A sandfly survey was performed between 2016 and 2018 in 10 municipalities categorised into three different environment types: (i) Conservation Unit (CUN)-comprised of preserved ombrophilous forests; (ii) Forest Edge (FE)-small forest fragments; and (iii) Peridomicile (PE)-areas around dwellings. FINDINGS A total of 73 species were identified from 9,535 sandflies. The most abundant species were Psychodopygus davisi (1,741 individuals), Nyssomyia antunesi (1,397), Trichophoromyia auraensis (1,295) and Trichophoromyia ubiquitalis (1,043). Diversity was the highest in CUN, followed by the FE and PE environments. One pool of Ps. davisi tested positive for Leishmania braziliensis, reinforcing the possibility that Ps. davisi acts as a vector. The cytochrome b (cytb) sequences were used to identify three blood meal sources: Bos taurus, Homo sapiens and Tamandua tetradactyla. MAIN CONCLUSIONS Our results demonstrated that sandflies can switch between blood meal sources in differing environments. This study enhances the knowledge of the vector life cycle in RO and provides information relevant to leishmaniasis surveillance.