Adão Celestino’s research while affiliated with Secretaria de Estado da Educação do Paraná and other places

The recent geographic spread of Leishmania infantum along the borders of Argentina, Brazil and Paraguay has been highlighted. In our previous study, Lutzomyia longipalpis was found in 55 of 123 patches surveyed, and in some patches, sandflies were found at higher densities, forming hotspots. Based on the One Health approach, we investigated the seasonality of the vector, the presence of parasite DNA, and the environmental factors that contribute to vector and parasite dispersal in these previously described hotspots in Foz do Iguaçu, Brazil. Entomological surveys were conducted monthly for one year. Fourteen hotspots peridomicile and six intradomicile were sampled. PCR was used to assess the prevalence of Leishmania DNA in sandflies. Zero-inflated negative binomial regression was used to determine the association of micro- and mesoscale environmental variables with the occurrence and abundance of the three most abundant sandfly species sampled. A total of 3543 species were captured, with Lutzomyia longipalpis being the predominant species (71.78%) of the 13 species found. Evandromyia edwardsi, Expapillata firmatoi, Micropygomyia ferreirana and Pintomyia christenseni were reported for the first time in the region. NDVI, distance to water, precipitation, west-to-east wind, wind speed, maximum and minimum relative humidity, and sex were significant variables associated with vector presence/abundance in the environment. Vector presence/abundance in the peridomicile was associated with precipitation, altitude, maximum temperature, minimum and maximum relative humidity, west-to-east wind, wind speed, and sex. Leishmania DNA was detected in an average of 21% of Lu. longipalpis throughout the year. Vector abundance is concentrated in urban and peri-urban areas, with some specimens present in different parts of the city and some sites with high vector abundance. This distribution suggests that the risk of actual contact between humans and parasite vectors in urban areas during the epidemic period is associated with patches of peri-urban vegetation and then extends into urban areas.

Background: The recent geographic expansion of Leishmania infantum vectors in the triple border area of Argentina, Brazil, and Paraguay has highlighted the need to know the seasonality, parasite infection rate, and the factors that contribute the dispersal and handling of this parasite. Methods: Entomological, quantitative longitudinal studies were conducted in Foz do Iguaçu, Brazil, where sand fly abundance was higher in cross-sectional studies. Monthly sand fly samplings occurred in 2014-2015. LeishmaniaDNA was detected by PCR and subsequently sequenced, classified, and the infection rate was estimated. The study also featured an observational and descriptive design. Environmental variables were analyzed at the micro- and mesoscales, and the data were evaluated along with entomological and infection inputs. Results: A total of 3,582 sand flies were caught. Lutzomyia longipalpiswas the predominant species (71.5%) among 13 species found in one year of sampling. Four species, Evandromyia edwardsi, Expapillata firmatoi, Micropygomyia ferreirana, and Pintomyia christenseni were reported for the first time. The NDVI, distance from water, sex, west-to-east wind, and wind speed were significant variables for the intra-environment presence and/or abundance of vectors. The presence and/or abundance of vectors in peri-domicile were influenced by rain, altitude, maximum temperature, minimum and maximum relative humidity, west-to-east wind, wind speed, and sex. Considering PCR positivity, females infected with L. infantum were found throughout the year, and especially with Lu. longipalpis (prevalence means of 16.4). Conclusions: Vector colonization concentrates on urban and peri-urban hotspot areas, with some individuals being present in various parts of the city and few sites showing high vector abundance. This distribution suggests that the risk of actual contact between humans and parasitic vectors in urban areas during the epidemic period is associated with patches of peri-urban vegetation and then spreads across urban areas. We can state that, in the period of this study, the most critical transmission phase for L. infantum in the region is from January to May. Therefore, future management plants to reduce access to reservoirs might reduce sand fly infection and consequently human and animal infections.

Every year about 3 million tourists from around the world visit Brazil, Argentina and Paraguay´s triple border region where the Iguaçu Falls are located. Unfortunately, in recent years an increasing number of autochthonous canine and human visceral leishmaniasis (VL) cases have been reported. The parasite is Leishmania (Leishmania) infantum and it is transmitted by sand flies (Phlebotominae). To assess the risk factors favorable for the establishment and spread of potential vectors the Centers for Disease Control and Prevention light trap (CDC-light trap) collections were made in the Foz do Iguaçu (FI) and Santa Terezinha de Itaipu (STI) townships and along two transects between them. Our study determined the Phlebotominae fauna, the factors that affect the presence and abundance of Lutzomyia longipalpis and Nyssomyia whitmani, the presence of L. infantum in different sand fly species and which Leishmania species are present in this region. Lutzomyia longipalpis was the prevalent species and its distribution was related to the abundance of dogs. Leishmania infantum was found in Lu. longipalpis, Ny. whitmani, Ny. neivai and a Lutzomyia sp. All the results are discussed within the Stockholm Paradigm and focus on their importance in the elaboration of public health policies in international border areas. This region has all the properties of stable VL endemic foci that can serve as a source of the disease for neighboring municipalities, states and countries. Most of the urban areas of tropical America are propitious for Lu. longipalpis establishment and have large dog populations. Pan American Health Organization´s initiative in supporting the public health policies in the border areas of this study is crucial and laudable. However, if stakeholders do not act quickly in controlling VL in this region, the scenario will inevitable become worse. Moreover, L. (Viannia) braziliensis found in this study supports the need to develop public health policies to avoid the spread of cutaneous leishmaniasis. The consequences of socioeconomic attributes, boundaries and frontiers on the spread of diseases cannot be neglected. For an efficient control, it is essential that urban planning is articulated with the neighboring cities.