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Background : The present study was carried out in the rural and urban area of Diamantina/Minas Gerais (MG), an endemic municipality for visceral leishmaniasis (VL) in Brazil. Methods : Patient notification records, canine prevalence, and phlebotomine fauna were evaluated. Results : In the period from 2016 to 2018, eight human cases were confirmed, with three deaths, predominantly in males. In the same period, a total of 1,388 dogs resided in the rural and urban area of the municipality were submitted to the DPP® and ELISA, with a percentage of confirmed canine cases of 29.9% and 29.4%, respectively. The entomological study conducted in the municipality revealed the presence of 10 species of sand flies, with a predominance of Lutzomyia longipalpis (55.75%), mainly in the rural area. Conclusions : Unlike what is happening in urban centers, the results of this study suggest that the VL in Diamantina is in the process of urbanization, given the high percentage of confirmed canine cases and the high density of Lu. longipalpis in the rural area of the municipality. These risk factors warn about the need for continuous surveillance and the need to control actions of VL in this area., (Copyright ©2021, Yale Journal of Biology and Medicine.)

The aim of this study was to identify blood meals of female sandflies captured in the municipality of Governador Valadares, an endemic area of visceral and cutaneous leishmaniasis, in the State of Minas Gerais, Brazil. From May 2011 to January 2012, captures were performed using HP light traps in four districts. There were 2,614 specimens (2,090 males and 524 females) captured; 97 engorged females were identified belonging to the species Lutzomyia longipalpis(82.1%) and Lutzomyia cortelezzii(17.9%). Considering simple and mixed feeding, the enzyme-linked immunosorbent assay revealed a predominance of chicken blood (43.6%) in Lutzomyia longipalpis, showing the important role that chickens exert around the residential areas of Governador Valadares. This finding increases the chances of sandflies contact with other vertebrates and consequently the risk of leishmaniasis transmission.

Background: Sand fly collections were performed to study ecological aspects of the Phlebotominae fauna of the Xakriabá Indigenous Reserve, an area with endemic cutaneous leishmaniasis, located in the state of Minas Gerais, Brazil., Methods: The collections were performed in peridomicile areas and along trails previously selected for the study of wild and synanthropic Leishmania hosts. Differences in the distribution patterns of the sand fly species as well as in species richness and abundance between the different ecotopes were investigated during both rainy and dry seasons over the course of the study period., Results: A total of 8,046 sand flies belonging to 11 genera and 28 species were collected. Lutzomyia longipalpis and Nyssomyia intermedia were the most abundant species in peridomicile areas, whereas Martinsmyia minasensis and Lutzomyia cavernicola were the most abundant species among the different trail ecotopes., Conclusion: The different composition of the sand fly fauna observed in the peridomicile areas and in the trails during the study, reinforces the importance of sampled different areas in a phlebotomine fauna survey. The presence of Lutzomyia longipalpis and Ny. Intermedia most abundant in peridomicile can be important to Leishmania infantum and Leishmania braziliensis transmission in the Imbaúbas native village.

This study investigated the sandfly fauna of two quartzite caves in the Espinhaço Mountain Range, located in the municipality of Diamantina, state Minas Gerais. From August 2010-July 2011, entomological sampling was performed in the caves of Salitre and Monte Cristo with two HP light traps exposed in the photic and aphotic zones of each cave. The sandfly fauna consisted of 17 species, among which Lutzomyia cipoensis was predominant (54.76%). The male/female ratio in the total captures was 1:2.5. The aphotic zone showed the highest frequency of specimens captured (65%). A greater density of sandflies occurred during the summer (January-February), coinciding with the period of higher temperatures, humidity and rainfall. The presence of Lutzomyia longipalpis, Lutzomyia whitmani and Lutzomyia pessoai, proven or suspected vectors of leishmaniasis, is of concern because the area is visited by many tourists.

A new species of Brazilian phlebotomine sandfly found in Brazil, municipality of Diamantina, state of Minas Gerais, is described based on males and females collected in a quartzite cave. The body of spermathecae is continuous to the individual duct, lanky and tapering at the end, with conical shaped, not striated and presenting the head with dense setae. The male presents gonostyle with four spines and a small subterminal seta and gonocoxite with one group of persistent setae. The paramere is simple with a group of small setae on the dorsal apex. The morphological features of this new species permit its inclusion in the migonei group.

The environmental changes resulting from the construction of hydroelectric dams may affect the fauna of insect vectors and consequently the epidemiology of the diseases they transmit. This work examined the mosquito and sand fly fauna in the area of the Aimorés hydroelectric power plant, analyzing the seasonal distribution and the degree of species synanthropy in different ecotopes. Between November, 2008 and September, 2009, entomological captures were performed with the help of HP light traps in the rural, urban, and forest areas of Aimorés, Ituêta, Resplendor, and Baixo Guandu counties. The fauna proved to be quite diversified. Twenty-two species of mosquitoes and 11 species of sand flies were found. Culex quinquefasciatus was predominant among mosquitoes (76.7%), while Lutzomyia intermedia prevailed among sand flies (34.5%). Some of the captured species have medical interest. Supported by the high degree of synanthropy, those species reinforce the need for epidemiological surveillance., (© 2012 The Society for Vector Ecology.)

Introduction: In the town of Porteirinha, State of Minas Gerais, 23 human cases of visceral leishmaniasis (VL) in 1998 and 1999 were recorded., Methods: A study was conducted involving the triad of action recommended for the control of VL. Patients were treated and serologically positive dogs were euthanized quarterly. The pyrethroid insecticide α-cypermethrin was applied in the neighborhoods where human cases were recorded., Results: A reduction in canine seroprevalence and sand flies occurred following the implementation of control measures, reflecting in a reduction in human cases of VL., Conclusions: The results show the efficiency of such control measures when used in association.

Introduction: A study on the phlebotomine sandfly fauna was carried out in an endemic area for American tegumentary leishmaniasis in the municipality of Governador Valadares, in the State of Minas Gerais, Brazil., Methods: Captures were undertaken using HP light traps in four districts, on three nights per month, for one year (from January to December 2008). Correlations between climatic factors (temperature, relative air humidity and rainfall) and the numbers of sandflies collected was observed., Results: 5,413 phlebotomine specimens were caught and were identified as belonging to 12 species. Of these specimens, 2,851 (52%) were females and 2,562 (48%) were males., Conclusions: Lutzomyia intermedia predominated (29.9% of the species caught), thus suggesting that they were responsible for transmission of American tegumentary leishmaniasis, together with L. whitmani, which was also found in the area (4.3%). The presence of L. longipalpis (11.9%), the main vector for visceral leishmaniasis in Brazil, is an important finding, which makes rigorous entomological surveillance of the area necessary.

Introduction: Visceral leishmaniasis has been notified in nearly all states of Brazil, and particularly in the north of Minas Gerais, where the disease is endemic. The aim of this study was to detect natural infection of Lutzomyia longipalpis and, through the PCR/RFLP technique, identify Leishmania species found in sandflies in the municipality of Janaúba., Methods: Using light traps, 1,550 females of L. longipalpis were caught and grouped into pools of 10 specimens to be subjected to DNA extraction and amplification, by means of generic PCR and cacophony., Results: Out of the 155 pools, six were positive for Leishmania sp., and thus the infection rate in the municipality was 3.9%. Through PCR/RFLP, the digestion pattern among the positive samples was found to be similar to that of the reference strain of Leishmania chagasi (MHOM/BR/74/PP75)., Conclusions: The detection of natural infection associated with studies on the epidemiology of visceral leishmaniasis suggests that L. longipalpis is involved in transmission of L. infantum chagasi in Janaúba, particularly in areas of intense transmission of visceral leishmaniasis.

In the present paper, we evaluate the relationship between climate variables and population density of Lutzomyia longipalpis in Montes Claros, an area of active transmission of American visceral leishmaniasis (AVL) in Brazil. Entomological captures were performed in 10 selected districts of the city, between September 2002-August 2003. A total of 773 specimens of L. longipalpiswere captured in the period and the population density could be associated with local climate variables (cumulative rainfall, average temperature and relative humidity) through a mathematical linear model with a determination coefficient (Rsqr) of 0.752. Although based on an oversimplified statistical analysis, as far as the vector is concerned, this approach showed to be potentially useful as a starting point to guide control measures for AVL in Montes Claros.

In Brazil, visceral leishmaniasis (VL) is caused by Leishmania chagasi parasites that are transmitted to man through the bites of infected females of Lutzomyia longipalpis sand flies. In order to evaluate transmission risk and to clarify the epidemiology of this tropical disease, studies focused on the vector and favorable environmental conditions are of fundamental importance. In this work, we surveyed the phlebotomine sand fly fauna in Janaúba, a Brazilian municipality that is endemic for VL. During a two-year period, entomological captures were performed monthly in 15 districts with high, moderate and low profiles of VL transmission. A total of 14,591 phlebotomine sand flies were captured (92% L. longipalpis), with a predominance of males. Most specimens were captured in the peri-domicile setting, although the number of specimens captured in the intra-domicile setting emphasises the anthropophilic behaviour of this insect. The population density of L. longipalpis was modulated by climate variations, particularly with clear increases immediately after the rainy season. However, the pattern of distribution did not coincide with the occurrence of human or canine cases of VL. This suggests that the eco-epidemiology of VL is particular to each area of transmission and must be taken into account during the design of public health control actions.

We surveyed the phlebotomine fauna in the Parque Nacional Cavernas do Peruaçu, Minas Gerais, Brazil, aiming to associate the presence of vector with the risk of leishmaniasis transmission. Field captures were performed with CDC light traps between February and March 2003. A total of 436 sand flies were captured, belonging to 14 species. The predominant species (28.7%) was Lutzomyia ischnacantha Martins, Souza e Falcão, followed by L. renei (27,06%) and L. cavernicola (13,07%). The finding of L. intermedia, a species that is incriminated as vector of cutaneous leishmaniasis, has to be taken into account.

During April and May 2006, experiments were carried out in Brejo do Mutambal, Varzelândia Town, Minas Gerais State, to evaluate the attractiveness of phlebotomine sandflies to CDC light traps, baited with kairomones. Of the 19 species of Lutzomyia already registered for the region, L. lutziana (Costa Lima), L. longipennis (Barreto), L. goiana (Martins, Falcão & Silva) and L. brasiliensis (Costa Lima) were recorded for the first time, thus increasing the diversity of phlebotomine sandflies fauna in this area to 23 species. The new registered species and distribution are shown and discussed herein.

Visceral leishmaniasis (VL) is a growing zoonosis with an increasing number of new cases and a rapid geographical spreading of the disease. In the present study, a canine survey was carried out in the city of Montes Claros (320,000 inhabitants), an endemic area of American visceral leishmaniasis in the state of Minas Gerais, Brazil. A total number of 4795 dogs were examined by serology, which showed a rate of seropositivity of 5%. Isoenzymatic analysis confirmed Leishmania infantum chagasi as the local aetiological agent of CVL. Canine tissues were assayed for the presence of Leishmania parasite DNA using different techniques. The infectivity of asymptomatic, oligosymptomatic and symptomatic seropositive dogs was tested by xenodiagnosis using laboratory reared Lutzomyia longipalpis. Rates of infection of 5.4%, 5.1% and 28.4% were found for the phlebotomine sand flies that fed in asymptomatic, oligosymptomatic and symptomatic dogs, respectively. Our results indicate that, under experimental conditions, symptomatic dogs are about four times more infective to VL vectors than oligosymptomatic or asymptomatic animals. The lower infectivity rates of dogs displaying any of the last two clinical forms of leishmaniasis, however, must be taken into account in the epidemiology of CVL.

Between January and December 2000, systematic monthly capture of phlebotomine sandflies was undertaken by means of light traps of CDC type in Brejo do Mutambal, an endemic area for American cutaneous leishmaniasis located in the municipality of Varzelândia, State of Minas Gerais. Nineteen phlebotomine species were captured, totaling 6,756 specimens. The species correlated with ACL transmission were captured in low numbers, as follows: Lutzomyia intermedia (5.1%), L. migonei (0.4%) and L. whitmani (0.1%). Lutzomyia longipalpis was the predominant species captured (34.8%), thus also suggesting a risk of visceral leishmaniasis transmission. The proportion of sandflies captured in areas surrounding homes was 91.7 % while 8.3% were captured inside homes. The interference of climatic factors (temperature, relative air humidity and rainfall) on phlebotomine population dynamics was evaluated.

Studies on the behavioral and feeding habits of some species of phlebotominae sand flies have contributed to the comprehension of the epidemiology of leishmaniasis. In the present work, systematic captures were performed monthly in the municipality of Porteirinha (MG) using 28 light traps (CDC) from January to December 2002. Fourteen different species of phlebotomine were captured in a total of 1,408 specimens. The highest percentage of individuals (53.3%) was collected in the peridomicile against 46.7% in the intradomicile. Lutzomyia longipalpis was the predominant species in that region. The blood feeding of 38 females of this species from the field was analyzed by precipitin reaction. The results indicated that Lutzomyia longipalpis is an opportunist (65.1%) species that feeds on a wide variety of vertebrates in nature.

Visceral leishmaniasis in Brazil was initially associated with rural areas. However, due to several environmental modifications such as deforestation, urbanization and intense migratory processes, there has been an expansion of endemic areas, leading to urbanization of the disease, mainly in the central and northeastern regions of Brazil. In the municipality of Montes Claros, located in the north of the state of Minas Gerais, an epidemiological survey on VL was carried out. A canine serological inquiry was carried out in 2002 and an entomological survey, using luminous CDC traps, was performed from September 2002 to August 2003. Canine VL prevalence showed an average infection rate of approximately 5%. An estimated 16 species comprised the phlebotomine sand fly fauna, based on a total of 1043 specimens. The predominant species was Lutzomyia longipalpis with a rate of 74%, suggesting its participation in the transmission of VL in the municipality of Montes Claros.

This paper describes a new model of light trap, named HP, based on the widely used CDC trap. Its advantages include high efficiency, easy handling and transport. Moreover, it is almost totally made of national materials, which reduces considerably the final cost.

A study on the phlebotomine sand fly fauna in Belo Horizonte city, state of Minas Gerais, Brazil, was carried out. From April 2001 to March 2003, monthly systematic collections were performed in three houses from each of the nine regions of the city, using CDC light traps for four consecutive days. The traps were set into the houses and in peridomestic areas totaling 54 traps. A number of 3871 sand fly specimens of the genera Lutzomyia and Brumptomyia were collected. Sixty eight percent of the specimens were L. longipalpis and 16% L. whitmani, insect vectors of visceral and American cutaneous leishmaniasis, respectively. Environmental factors such as temperature, humidity, and frequency of precipitation suggest that the number of insects increases after rainy periods. During the same period mentioned above, seasonal captures were carried out in parks and green areas of Belo Horizonte, using Shannon trap. A total of 579 phlebotomine sand flies were collected from which 398 (68.7%) were females with the predominance of L. whitmani and L. monticola. Those specimens were used for natural infection examination, by polymerase chain reaction. No Leishmania DNA was present in any of the specimens tested.

A study of the phlebotomine sand fly fauna was carried out in an endemic area of American visceral leishmaniasis (AVL) in the municipality of Porteirinha, in the Brazilian state of Minas Gerais. Captures were performed with CDC light traps in 7 districts, 5 days per month, during 2 consecutive years (January 2000 to December 2001). A total of 3240 sand flies were captured and identified. Sixteen species were found, among which 15 belonged to the genus Lutzomyia and one to the genus Brumptomyia. Lutzomyia longipalpis, a proven vector of AVL, was the predominant species (71.85%) throughout the time period. The interference of climatic factors (temperature, humidity, and rainfall) over the populational dynamics of the sand flies was determined. Statistical analysis of the data showed a significant correlation among the number of phlebotomine sand flies collected, rainfall, and humidity, whereas the effect of temperature was negligible, in that particular region. The amount of collected phlebotomine, the number of human cases, and the prevalence of canine AVL in the districts of Porteirinha are discussed.

A morphometric survey examined adult specimens of Lutzomyia whitmani (Antunes & Coutinho) captured at 5 municipalities in southeastern and northeastern Brazil to compare the populations. The localities were Ilhéus (Bahia), Martinho Campos (Minas Gerais), Corte de Pedra (Bahia), Baturité (Ceará), and Amaraji (Pernambuco): all are known foci of American cutaneous leishmaniasis. Fifteen males and 15 females from each population were analyzed morphometrically for 42 and 37 characters, respectively. Statistical data alone were insufficient to discriminate among the 5 populations. Further analysis generated phenograms that indicated there were 2 spatial clusters: the 1st was composed of specimens from Ilhéus (Bahia) and Baturité (Ceará) and the 2nd of specimens from Martinho Campos (Minas Gerais), Corte de Pedra (Bahia), and Amaraji (Pernambuco). Although insufficient to define the taxonomic status of the populations studied, the results delineated the existence of biogeographical structuring within L. whitmani. Complementary studies on the susceptibility to Leishmania braziliensis infection in the 5 populations are in progress to clarify the relationship between the 2 biogeographical clusters and American cutaneous leishmaniasis transmission in those Brazilian regions.