Detection of Saint Louis encephalitis virus in two Brazilian states.

We describe the circulation of Saint Louis encephalitis virus (SLEV) in two Brazilian States during outbreaks of Dengue and Zika viruses. We detected the virus in a patient from Araraquara, State of São Paulo, and in patients and in a mosquito pool of Culex quinquefasciatus from Sinop, State of Mato Grosso. Phylogenetic analysis grouped samples from this study within genotype V, which are closely related to other strains that previously circulated in other parts of the country. Genotype V seems to have established circulation in Brazil.

Detection of the Asian II genotype of dengue virus serotype 2 in humans and mosquitoes in Brazil.

INTRODUCTION: DENV-2 is the cause of most dengue epidemics worldwide and is associated with severe cases. METHODS: We investigated arboviruses in 164 serum samples collected from patients presenting with clinical symptoms of dengue fever and 152 mosquito pools. RESULTS: We detected the Asian II genotype of DENV-2 in humans and mosquitoes. Our results confirmed the circulation of the Asian II genotype in Brazil, in addition to the prevalent Asian/American genotype. CONCLUSIONS: The detection of Asian II genotype of DENV-2 in mosquito pools collected in a forest park may be related to a spillback event of human dengue virus.

Ecological aspects of potential arbovirus vectors (Diptera: Culicidae) in an urban landscape of Southern Amazon, Brazil.

Amazon has been under intense human pressure, especially in the so-called "Arc of Deforestation" in the Eastern and Southern regions. Changes in biodiversity due to landscape disturbance in municipalities at the Arc of Deforestation are likely to impact mosquito species leading to the potential for emergence of arboviruses. Our aim was to describe the composition and structure of culicids in Sinop, a municipality located in the Southern Amazon at the State of Mato Grosso, as well as their presence in urban habitats, analyzing climate variables and potential risk of arbovirus transmission. Mosquitoes were collected in four habitats located in urban environments for 12 months. We recovered 5,210 adult mosquitoes from mosquito traps. Among the 33 species identified, 19 are associated with arbovirus transmission. Higher abundance, richness, diversity, and equitability of mosquito species were observed in urban forest parks and in new neighborhoods located in the outskirts of the city, nearby forest fragments and agricultural areas. As the environment consolidates as urban, both abundance and richness decrease. Highly urbanized neighborhoods had higher dominance of Culex quinquefasciatus, a mosquito associated with different arboviruses, including West Nile and Saint Louis encephalitis virus. The medically important species Cx. declarator, Cx. (Melanoconion) ssp., Aedeomyia squamipennis and Aedes scapularis were found in the four habitats. It is possible that these mosquitoes are adapting to different habitats and as a consequence, they are reaching urbanized areas. Mosquito abundance was higher in the days of high temperature and low precipitation in urban forest parks and in highly urbanized neighborhoods. These results suggest that Sinop region is a key area for surveillance of arbovirus vectors.

Detection of the Asian II genotype of dengue virus serotype 2 in humans and mosquitoes in Brazil

Abstract INTRODUCTION: DENV-2 is the cause of most dengue epidemics worldwide and is associated with severe cases. METHODS: We investigated arboviruses in 164 serum samples collected from patients presenting with clinical symptoms of dengue fever and 152 mosquito pools. RESULTS: We detected the Asian II genotype of DENV-2 in humans and mosquitoes. Our results confirmed the circulation of the Asian II genotype in Brazil, in addition to the prevalent Asian/American genotype. CONCLUSIONS: The detection of Asian II genotype of DENV-2 in mosquito pools collected in a forest park may be related to a spillback event of human dengue virus.

Validation of phlebotomine cardinal temperatures and humidities in the region of Rio Arinos, Mato Grosso, Brazil

The purpose of this study was to validate the phlebotomine cardinal temperatures and humidities, reported by Campelo Júnior et al. (2014), using different collection data, obtained in a study on the number of these insects, captured in the Arinos region, in Nova Mutum, Mato Grosso, Brazil, according to spatial (100 m to 1000 m) and temporal (June 2011 to April 2012) variability. Phlebotomines were captured in the riparian forest, by means of 10 traps positioned approximately every 100 m, northwards from the road along the river bank, with samples obtained bimonthly during three consecutive nights for a period of 12 months. Average relative humidity and temperature during the periods when the traps remained at the collection points were measured using a digital thermometer-hygrometer. The phlebotomine sand fly fauna was highly diversified, presenting 31 species, of which Lutzomyia antunesi was the most prevalent (45.4%). L. flaviscutellata, L. whitmani and L. umbratilis, known vectors of Leishmania spp., were also found. There was a marked variation in the quantity of phlebotomines captured throughout the consecutive collection days, as each sampling was affected by different factors determining a different maximum value for the number of insects present in each situation, as demonstrated for temperature and air humidity.

Aspects on the ecology of phlebotomine sand flies and natural infection by Leishmania hertigi in the Southeastern Amazon Basin of Brazil.

The medical and veterinary importance of sand flies (Diptera: Psychodidae) follow as a result of some species ability to transmit the zoonotic protozoa of the genus Leishmania. Of all municipalities in the state of Mato Grosso, Sinop ranks first in reported cases of American Cutaneous Leishmaniasis (ACL). Sinop urban zone encompasses three permanent forest preservation areas (APPs) that provide refuge for insects and other vertebrate hosts. We assessed ecological parameters and investigated the natural infection by Leishmania spp. of the phlebotomine fauna from four ecotypes with different levels of urbanization in the urban area of Sinop. A total of 62,745 sand flies were collected, of which 52.34% female. Out of 37 species in this study, nine were found to be constant. Sand flies frequency and diversity were highest in APPs (96.85%; 33 species). Lutzomyia dasypodogeton was the most frequent species and exhibited the greatest abundance (SISA=0.977). The neighborhoods around APPs and completely urbanized neighborhoods presented noteworthy ecological similarity. Moreover, eight vector sand fly species with medicalwere identified, and one L. antunesi sample pool was found to be naturally infected with Le. hertigi. We observed a high frequency and diversity of sand flies, including some species that are known to be major vectors of ACL. Further studies are needed on the natural rates of infection in humans, domestic animals, and sylvatic hosts to better comprehend the leishmaniases dynamics.

Frequency and diversity of phlebotomine sand flies (Diptera: Psychodidae) in Sinop, State of Mato Grosso, Brazil.

INTRODUCTION:: Understanding the diversity of sand flies is important for the epidemiology and control of leishmaniasis. This study aimed to understand the frequency, diversity, and seasonality of medically important sand flies in the municipality of Sinop, State of Mato Grosso, Brazil. METHODS:: The study was conducted in an urban area, including four ecotypes with different levels of urbanization. The sand flies were collected using light traps for three nights per month, from May 2014 to April 2015. RESULTS:: A total of 62,745 sand flies was collected, 52.34% of which were female. The frequency and diversity of sand flies was the highest in areas of permanent preservation (APPs) (96.85%), and was lower in more urbanized areas. Lutzomyia dasypodogeton was the most frequent species in the APPs. Lutzomyia antunesi was the most frequent in neighborhoods with forest fragments and neighborhoods around APPs, and L. aragaoi was the most frequent in completely urbanized neighborhoods. A higher frequency and diversity of sand flies was observed in the rainy season (87.92%) than in the dry season (12.08%). Eight medically important species were captured, and Lutzomyia antunesi, which is associated with American cutaneous leishmaniasis and visceral leishmaniasis, was observed in all ecotypes throughout the year. CONCLUSIONS:: We observed a high frequency and diversity of sand flies in all urban areas, and some species collected were major vectors of leishmaniasis. These results support the need for further studies of the natural rates of infection of these insects and the circulation of the disease in hosts and vectors.

Frequency and diversity of phlebotomine sand flies (diptera: psychodidae) in sinop, state of Mato Grosso, Brazil

Abstract INTRODUCTION: Understanding the diversity of sand flies is important for the epidemiology and control of leishmaniasis. This study aimed to understand the frequency, diversity, and seasonality of medically important sand flies in the municipality of Sinop, State of Mato Grosso, Brazil. METHODS: The study was conducted in an urban area, including four ecotypes with different levels of urbanization. The sand flies were collected using light traps for three nights per month, from May 2014 to April 2015. RESULTS: A total of 62,745 sand flies was collected, 52.34% of which were female. The frequency and diversity of sand flies was the highest in areas of permanent preservation (APPs) (96.85%), and was lower in more urbanized areas. Lutzomyia dasypodogeton was the most frequent species in the APPs. Lutzomyia antunesi was the most frequent in neighborhoods with forest fragments and neighborhoods around APPs, and L. aragaoi was the most frequent in completely urbanized neighborhoods. A higher frequency and diversity of sand flies was observed in the rainy season (87.92%) than in the dry season (12.08%). Eight medically important species were captured, and Lutzomyia antunesi, which is associated with American cutaneous leishmaniasis and visceral leishmaniasis, was observed in all ecotypes throughout the year. CONCLUSIONS: We observed a high frequency and diversity of sand flies in all urban areas, and some species collected were major vectors of leishmaniasis. These results support the need for further studies of the natural rates of infection of these insects and the circulation of the disease in hosts and vectors.

Phlebotomine sandfly fauna and natural Leishmania infection rates in a rural area of Cerrado (tropical savannah) in Nova Mutum, State of Mato Grosso in Brazil.

INTRODUCTION: American cutaneous leishmaniasis (ACL) has been reported in every municipality of the State of Mato Grosso, Brazil, but the transmission epidemiology remains poorly understood. Our study was developed in a rural area of the Nova Mutum municipality where four autochthonous cases of ACL were reported in 2009. Our aims were to describe the local phlebotomine sandfly fauna and to investigate the infection rates and infecting Leishmania species in the captured sandflies. METHODS: Entomological captures were performed bimonthly at 10 fixed sites close to the edge of a forested area between June 2011 and April 2012. RESULTS: A total of 3,743 phlebotomine sandflies belonging to 31 distinct species were captured. Approximately 75% of the specimens were females. The most abundant species (45.4%) was Lutzomyia antunesi, which was consistently captured at every site. Species that are epidemiologically important for ACL, such as L. flaviscutellata, L. whitmani and L. umbratilis, were also captured. L. antunesi and L. ubiquitalis were naturally infected by Leishmania braziliensis or Le. guyanensis, with minimum infection rates of 0.88% and 6.67%, respectively. Surprisingly, L. antunesi was infected by Le. infantum (synonym chagasi). CONCLUSIONS: The natural infection of L. antunesi and L. ubiquitalis by Leishmania sp. suggests that these species might play a role in the zoonotic cycle of ACL in Nova Mutum. The presence of Le. infantum in L. antunesi suggests that there may be a risk of an outbreak of visceral leishmaniasis (VL) in Nova Mutum.

Phlebotomine sandfly fauna and natural Leishmania infection rates in a rural area of Cerrado (tropical savannah) in Nova Mutum, State of Mato Grosso in Brazil

Introduction American cutaneous leishmaniasis (ACL) has been reported in every municipality of the State of Mato Grosso, Brazil, but the transmission epidemiology remains poorly understood. Our study was developed in a rural area of the Nova Mutum municipality where four autochthonous cases of ACL were reported in 2009. Our aims were to describe the local phlebotomine sandfly fauna and to investigate the infection rates and infecting Leishmania species in the captured sandflies. Methods Entomological captures were performed bimonthly at 10 fixed sites close to the edge of a forested area between June 2011 and April 2012. Results A total of 3,743 phlebotomine sandflies belonging to 31 distinct species were captured. Approximately 75% of the specimens were females. The most abundant species (45.4%) was Lutzomyia antunesi, which was consistently captured at every site. Species that are epidemiologically important for ACL, such as L. flaviscutellata, L. whitmani and L. umbratilis, were also captured. L. antunesi and L. ubiquitalis were naturally infected by Leishmania braziliensis or Le. guyanensis, with minimum infection rates of 0.88% and 6.67%, respectively. Surprisingly, L. antunesi was infected by Le. infantum (synonym chagasi). Conclusions The natural infection of L. antunesi and L. ubiquitalis by Leishmania sp. suggests that these species might play a role in the zoonotic cycle of ACL in Nova Mutum. The presence of Le. infantum in L. antunesi suggests that there may be a risk of an outbreak of visceral leishmaniasis (VL) in Nova Mutum. .