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Visceral leishmaniasis (VL) is endemic to many states in Brazil. To prevent further expansion of the disease, the Brazilian Ministry of Health adopted integrated measures through the Program of Surveillance and Control of Visceral Leishmaniasis (PSCVL), whose actions include the diagnosis and euthanasia of seropositive dogs (the main domestic reservoirs), the use of residual insecticides, environmental management (EM) to control vector population (mainly Lutzomyia longipalpis phlebotomine), rigorous epidemiological surveillance, and health education. The present study was conducted in areas with recent moderate VL transmission to evaluate the efficacy of vector control activities. The systematic capture of phlebotomine was performed for three consecutive days per month, from August 2015 to July 2017. The number of specimens captured was taken as a representative of the monthly insect population. A total of 38,055 phlebotomine specimens were captured and identified at the species level. Lu. longipalpis was consistently found to be the predominant species (97.7%) each month. In the first year of the study, no intervention was performed. In the second year, two cycles of chemical spraying, EM, or a combination of both were performed before and after the rainy season. All interventions, either individually or in combination, reduced the abundance of Lu. longipalpis in the study area.

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.

Leishmaniases are vector-borne diseases that are transmitted to humans through the bite of Leishmania-infected phlebotomine sand flies (Diptera:Psychodidae). The main proved vector of visceral leishmaniais (VL) in the New World - Lutzomyia longipalpis - is well-adapted to urban areas and has extensive distribution within the five geographical regions of Brazil. Integrated public health actions directed for the vector, domestic reservoir and humans for the control of VL are preferentially applied in municipalities with higher epidemiological risk of transmission. In this study, we evaluated the individual impact of two main vector control actions - chemical spraying and environmental management - in two districts with no reported cases of human VL. Although belonging to an endemic municipality for VL in Brazil, the integrated control actions have not been applied in these districts due to the absence of human cases. The number of L. longipalpis captured in a two-year period was used as indicator of the population density of the vector. After chemical spraying a tendency of reduction in L. longipalpis was observed but with no statistical significance compared to the control. Environmental management was effective in that reduction and it may help in the control of VL by reducing the population density of the vector in a preventive and more permanent action, perhaps associated with chemical spraying.

This report describes the stege I/II development of a new direct agglutination test (DAT) for the diagnosis of canine visceral leishmaniasis (CVL) using freeze-dried antigen produced Coomassie blue-stained Leishmania (Leishmania) infantum promastigotes. In stage I, 16 canine serum samples, collected from eight dogs carrying CVL and eight healthy dogs, were assessed with the DAT using 2-mercaptoethanol (2-ME), N-acetyl-cysteine (NAC), kaolin or NAC plus urea (NAC+U) to improve the assay conditions. Stage II assessed the diagnostic accuracy with 100 serum samples collected from dogs with symptomatic CVL and clinically healthy dogs, comparing the four different sample diluents. The CVL-DAT prototype kit showed equivalent performances when 2-ME, NAC or NAC+U were used: 97.1% sensitivity (CI: 83-99.8%), 97% specificity (CI: 88.5-99.5%) and a 97% diagnostic accuracy (CI: 90.8-99.2). With kaolin, a 94.1% sensitivity (CI: 79-99%), 97% specificity (CI: 88.5-99.5%) and 96% diagnostic accuracy were observed (CI: 89.5-98.7), with no statistically significant differences among the four reagents (p=1.0). The NAC plus urea in sample diluent decreased non-specific agglutination, promoted a better defined sharp-edged blue spot and was thus chosen as a component for the new DAT prototype to diagnose canine VL, designated DAT-Canis.

Background: A canine vaccine remains a promising approach for effective control of visceral leishmaniasis(VL), given its complex epidemiology in areas where zoonotic VL is prevalent. Leish-Tec®is a recombi-nant vaccine, based on the Leishmania A2 antigen, against canine VL (CVL). It is, since 2014, the singlecommercial vaccine licensed in Brazil. Here, Leish-Tec®efficacy was estimated through a randomizedfield trial (RFT), in a highly VL endemic area.Methods: The RFT was conducted from 2008 to 2010 in an endemic area of southeastern Brazil, presentinga CVL seroprevalence of 41.9%. Eight hundred forty-seven seronegative dogs were randomly selected toreceive Leish-Tec®(n = 429) or placebo (n = 418). Animals were followed up by clinical, serological, andparasitological exams for 18 months. The CVL incidence in both groups was compared through proportionanalysis.Results: A significant reduction in the number of cases of CVL was observed in the vaccine group, ascompared with the placebo group, whether efficacy was estimated according to parasitological results(71.4%; 95% CI: 34.9–87.3%; p = 0.001; risk ratio = 0.287), by adding results of xenodiagnosis and parasito-logical exams (58.1%; 95% CI: 26.0–76.3%; p = 0.002; risk ratio = 0.419). Among the animals that convertedto a positive anti-A2 serology, efficacy reached 80.8% (95% CI: 37.6–94.1%, p = 0.001; risk ratio = 0.192).Xenodiagnosis has detected a reduction of 46.6% (p = 0.05) in transmission to sand flies from vaccinatedanimals presenting anti-A2 positive serology.Conclusion: The Leish-Tec®vaccine proved significantly effective for prophylaxis of CVL, after naturalchallenge assured by transmission of Leishmania parasites, in a highly endemic area. Noteworthy, thisreport has unveiled the complexity of performing a RFT for anti-CVL vaccines in Brazil, which may behelpful for designing of future studies.

The present study was developed in the urban area of Paracatu, an endemic city for the American visceral leishmaniasis in Brazil. A six-month canine survey was performed with 6295 domiciled dogs in 28 districts in that area and showed that 4.2% of those (267 dogs) were positive for VL by ELISA and IFAT serum assays. Prevalence ratios for canine VL varied between 1.2% and 16.1%, depending on the district under investigation. Fifteen dogs - 80% of which were clinically asymptomatic for VL - were submitted to a more detailed study that comprised direct parasitological examination and Leishmania kDNA amplification of tissue samples as well as two PCR-RFLP methods using myelocultures. Leishmania amastigotes or Leishmania DNA were detected in all dogs but one. The infecting species of Leishmania was identified in about 50% (7/15) of the sample dogs: Leishmania (Leishmania) chagasi in two of them and, unexpectedly, Leishmania (Leishmania) amazonensis in the remaining five. Three months after the end of confiscation and elimination of the VL-seropositive dogs in the 28 districts of Paracatu, a systematic entomological survey was performed in five of them. Six hundred and sixty five (665) phlebotomine sand flies were captured in total, from which 89.5% were identified as Lutzomyia longipalpis. The population density of that species increased during the rainy season. Other thirteen (13) species of phlebotomine sand flies were captured at varying percentages from 0.2 to 5.0%. It is worth noting that L. longipalpis females were predominantely intradomicile when compared to males, suggesting that the VL transmission cycle in Paracatu may be occurring inside home.

We detected an outbreak of American cutaneous leishmaniasis in the Jequitinhonha River Valley, Minas Gerais, Brazil. Clinical and epidemiological aspects were studied for a period of two years. Data include results of physical examinations, Montenegro skin test and serology. In total 72 of the 299 individuals evaluated presented active lesions. Only one case out of these 72 patients showed the mucosal form of the disease. The precarious sanitary conditions, low educational level and low income found in the population studied demonstrated that, as with the other parasitic diseases, cutaneous leishmaniasis occurs with greater frequency in needy populations. A canine serological survey detected 20.3% (30/148) of dogs reactive to the Leishmania antigen. Lutzomyia intermedia was the predominant phlebotomine species and the majority of the specimens (84.9%) were captured in the peridomicile. Four samples from human and three from canine cases were isolated and characterised by PCR and isoenzymes as being Leishmania (Viannia) braziliensis. The peridomiciliary nature of the disease is discussed.

The association between the prevalence of infestation by Rhipicephalus sanguineus and Ctenocephalides felis felis and the presence of anti-Leishmania antibodies has been evaluated in dogs located in a city of Brazil endemic for canine visceral leishmaniasis. Blood samples from 5556 domestic dogs domiciliated in the urban area of Belo Horizonte (Minas Gerais state) were submitted to enzyme linked immunosorbent (ELISA) and indirect immunofluorescent antibody (IFAT) assays, and 432 (7.8%) animals tested positive. Seropositive (n=200) and seronegative (n=200) dogs were randomly selected and examined for the presence of ticks and fleas, the results of which were expressed qualitatively as infested or non-infested, irrespective of the intensity of infestation. The prevalence of infestation by R. sanguineus was significantly greater (ρ=0.04) among seropositive dogs (38.5%) compared with their seronegative counterparts (29.0%). Similarly, the prevalence of infestation by C. felis felis was significantly greater (ρ