Molecular detection of Leishmania and blood meal analysis in sand flies from Corumbá, Mato Grosso do Sul, Brazil.

In this study, we investigated the presence of Leishmania in sand flies collected from a peridomestic area in Corumbá, Mato Grosso do Sul, after an autochthonous case of cutaneous leishmaniasis was confirmed. A total of 1,542 sand flies belonging to seven species were collected, with Lu. cruzi being the most prevalent (94.3%). We detected the presence of DNA from Le. infantum (7 pools) and Le. braziliensis (3 pools) by sequencing the ITS1 amplicon in ten pools, all of which were composed of engorged (3) and non-engorged (7) females of Lu. cruzi. We collected 24 engorged females, with Homo sapiens being the most common blood meal source (91.6%), followed by Dasyprocta azarae and Canis lupus familiaris (4.2% each). To our knowledge, this is the first molecular evidence of Le. braziliensis in wild-caught Lu. cruzi in Brazil, suggesting its potential role as a vector for this parasite.

Geographic distribution of human leishmaniasis and phlebotomine sand flies in the State of Mato Grosso do Sul, Brazil.

BACKGROUND: In the State of Mato Grosso do Sul, Brazil, sand flies and cases of visceral (VL) and cutaneous (CL) leishmaniases have been reported in almost all municipalities. The aim of this study was to analyze the geographic distribution of VL and CL in relation the sand fly species found in the municipalities of Mato Grosso do Sul. METHODS: We analyzed VL and CL cases from 2001 to 2018 using data from the Notifiable Diseases Information System (SINAN). Data collected since 2003 on the presence of sand fly vectors (proven or suspected) were provided by the State Health Secretariat. RESULTS: A total of 3566 and 3030 cases of VL and CL, respectively, were reported from 2001 to 2018. The municipalities with the most reported cases of VL were Campo Grande (2495), Três Lagoas (442), Corumbá (140) and Aquidauana (136); and those for CL were Campo Grande (635) and Bodoquena (197). The following sand fly species with vector potential were found in 59 municipalities (74.7%): Lutzomyia longipalpis, Lutzomyia cruzi, Nyssomyia whitmani, Migonemyia migonei, Nyssomyia neivai, Pintomyia pessoai, Bichromomyia flaviscutellata and Pintomyia fischeri. Sand flies were present in six municipalities where no cases of VL were reported and in two municipalities where no cases of CL were reported. CONCLUSIONS: Our results indicate that the geographical distribution of VL and CL in Mato Grosso do Sul expanded during the study period, and highlight the presence of sand fly vectors in municipalities where these diseases are currently considered to be non-endemic.

Sand Fly Fauna, Spatial Distribution of Lutzomyia longipalpis (Diptera: Psychodidae), and Climate Factors in Dourados, Brazil.

Studies of the geographic distribution of sand flies and the factors associated with their occurrence are necessary to understand the risk of leishmaniasis transmission. The objective of this study was to characterize the sand fly fauna, particularly the spatial distribution of Lutzomyia longipalpis (Lutz & Neiva), and correlate these with climate factors in the Dourados municipality, Brazil. The collection of sand flies was carried out with CDC Light Traps over two periods: at six sites for three consecutive nights each month from August 2012 to July 2013; and at four other sites for two consecutive nights each month from April 2017 to February 2018. We collected 591 sand flies in the first period and 121 in the second period for a total of 712 sand flies; 697 of the total collected were Lu. longipalpis. The minimum and maximum sand fly infestation rate (sites with vector presence) was 11.1% and 83.33% in the first period, and 0% and 50.0% in the second period. No sand flies with Leishmania were identified via PCR. Lu. longipalpis presented an aggregate disposition with excellent adjustment. Rainfall and relative humidity were the abiotic factors that influenced the vector infestation level. The aggregate distribution for this species was predicted by the environmental factors that favor the proliferation of Lu. longipalpis. The results of this study should assist in devising measures to control sand flies in Dourados, Brazil.

Phlebotomine (Diptera: Psychodidae) fauna in a cavern containing cave paintings and its surrounding environment, Central-West Brazil.

The interior of caves usually presents climate, light, soil, flora and fauna that distinguish it from the external environment. Among the sandfly species found in caves, several may act as vectors of Leishmania spp. and others are a nuisance to humans due to their painful bites. This study sought to identify the phlebotomine fauna in a cavern with cave paintings ("Gruta do Pitoco") which attract tourists in Alcinopólis municipality, Mato Grosso do Sul state, Brazil. The sandflies were collected from March 2014 to September 2015, with automatic light traps, installed monthly, in the entrance and interior of the cave and outside it. A total of 7645 specimens belonging to 27 species were collected. Lutzomyia dispar, Martinsmyia oliverai and those of the Lu. longipalpis complex (Lu. cruzi and Lu. longipalpis) were the predominant species. Among the three environments sampled, no great difference between species richness was observed. Comparing these environments, the interior of the cave presented the lowest diversity index due to the high frequency of Lu. dispar (46%). For the first time, specimens (only females) of the genus Deanemyia were collected in Mato Grosso do Sul state. Moreover, the study revealed the sympatric occurrence of Lu. cruzi and Lu. longipalpis, both proven vectors of L. infantum, and also Lu. dispar, a highly anthropophilic species, which often causes annoyance to those who visit the cave.

High molecular prevalence of Leishmania in phlebotomine sand flies fed on chicken blood in Brazil.

Leishmaniases are endemic in Brazil, where Leishmania infantum has been detected in humans, dogs, cats, and phlebotomine vectors. Monitoring synanthropic vector populations is critical for leishmaniasis control-surveillance in such transmission-prone areas. Here, a suite of molecular approaches were used to assess Leishmania infection prevalence and to identify blood-meal sources in a large sample of sand flies collected in anthropic environments of a Leishmania-transmission area in Mato Grosso do Sul State (Rio Verde de Mato Grosso municipality), Central-West Brazil. We sampled sand flies monthly (January-June 2014 and 2016) in one peri-domestic site within each of six neighborhoods with recent records of human visceral and/or tegumentary leishmaniasis. kDNA-qPCR plus rDNA ITS-sequencing were used to detect and identify Leishmania in pooled female sand flies. Individual engorged females (n = 58) were used for blood-meal analyses through High-Resolution Melting (HRM) targeting the mtDNA cytb gene. Overall, 90.5% of 420 CDC trap-nights yielded vectors, for a total catch of 24,989 sand flies. We sub-sampled and identified 3088 sand flies of 12 species, including 2775 Lutzomyia longipalpis (the most abundant species at all sampling sites) and 297 Nyssomyia whitmani. Female sand flies (n = 1261) were grouped in 159 pools, of which 92 Lu. longipalpis (minimum infection rate [MIR] 8%) and 7 Ny. whitmani pools (MIR 7%) were Leishmania kDNA-positive. Most positive Lu. longipalpis were collected in the 2016 rainy season. Sequencing confirmed L. infantum in Lu. longipalpis samples. HRM analyses identified chicken DNA in 57 sand flies (98.3%), 37 of which were Leishmania DNA-positive (64.9%); human blood was found in just one (Leishmania-negative) female. Our data show ongoing risk of L. infantum transmission to humans in the study area, where Leishmania-infected sandfly vectors are common and heavily rely on chicken blood in the peri-domestic environment.

Description of Evandromyia (Aldamyia) orcyi, a new phlebotomine species (Diptera: Psychodidae: Phlebotominae) from the State of Mato Grosso do Sul, Brazil.

BACKGROUND: The genus Evandromyia is widely found in Brazil, but occurs mainly in Brazilian savannah. To date 13 species have been described in the subgenus Aldamyia. Here we described a new species of Evandromyia (Aldamyia) collected in the State of Mato Grosso do Sul, Brazil. METHODS: Measurements were made using a micrometer eyepiece on an Olympus CH-2 binocular microscope and drawings were executed with the aid of a camera lucida. RESULTS: The new species, Evandromyia orcyi sp. nov., is closely related to Evandromyia lenti, Evandromyia carmelinoi and Evandromyia evandroi, however, characteristics of the male terminalia and female spermathecae distinguish it from other species of the genus Evandromyia. CONCLUSION: With the description of Evandromyia orcyi sp. nov., six species of the subgenus Aldamyia have been reported from the State of Mato Grosso do Sul.

[Spatial distribution of Aedes albopictus in the southern area of Mato Grosso do Sul State, Brazil]. / Distribuição espacial de Aedes albopictus na região sul do Estado de Mato Grosso do Sul.

OBJECTIVE: To investigate the spatial distribution of Aedes albopictus population to provide input for developing sampling plans and supporting decision making on the control of this vector in field sampling. METHODS: A study was carried out in an urban area that has a vestige of primary vegetation, 20 km away from Dourados, Midwestern Brazil. Ten samplings were conducted between January 28, 2003 and April 9, 2003, using ovitraps which were monitored once a week, and distributed in a fixed sample area with 10 collection points for each sampling 300 m away from each other. Aggregation indexes were calculated and adjusted to the following theoretical frequency distribution: negative binomial, positive binomial and Poisson's. RESULTS: The sample variance was higher than the sampling mean, resulting in mean-variance indexes above the unit (32.066, 29.410, 14.444, 58.840, 56.042, 111.262, 70.140, 50.701, 93.221 and 8.481). Morisita's index was also statistically above the unit in all samplings (6.275, 3.947, 1.484, 3.725, 3.014, 5.450, 3.214, 3.886, 3.954 and 5.810), and K parameter ranged 0 and 8 (0.174, 0.309, 1.867, 0.332, 0.449, 0.203, 0.408, 0.314, 0.306 and 0.200). The Chi-square test for adjustment to the negative binomial distribution, positive binomial distribution, and Poisson's distribution was not statistically significant. CONCLUSIONS: Ae. albopictus population in the studied municipality showed an aggregated standard spatial distribution. This means that when individual vectors are found in a certain site, it is likely that other vectors can be found in the proximities, recommending insecticide spraying for vector control in this site without requiring sampling other sites in this same locality.