Current and Future Niche of North and Central American Sand Flies (Diptera: Psychodidae) in Climate Change Scenarios

Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector’s ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys’ ENM and human exposure to vectors of Leishmaniases

Climate Change Influences on Global Distributions of Dengue and Chikungunya Virus Vectors

This packet presents raster data files that accompany a manuscript submitted for publication to Philosophical Transactions of the Royal Society, titled “Climate Change Influences on Global Vector Distributions for Dengue and Chikungunya Viruses.” Included within this packet are the following data sets: • bias_layer.tif – This data layer summarizes the intensity with which Aedes mosquitoes have been sampled worldwide, according to the digital data resources that were accessed for this study. This data layer was used as a ‘bias layer’ with which to guide background sampling in the Maxent algorithm. • aegypti_present.tif – Ecological niche model for Aedes aegypti under present-day conditions. • aegypti_a1b.tif – Ecological niche model for Aedes aegypti calibrated under present-day conditions, but transferred to SRES A1B conditions for 2050 (see text for details) • aegypti_a2.tif – Ecological niche model for Aedes aegypti calibrated under present-day conditions, but transferred to SRES A2 conditions for 2050 (see text for details) • aegypti_b1.tif – Ecological niche model for Aedes aegypti calibrated under present-day conditions, but transferred to SRES B1 conditions for 2050 (see text for details) • albopictus_present.tif – Ecological niche model for Aedes albopictus under present-day conditions. • albopictus_a1b.tif – Ecological niche model for Aedes albopictus calibrated under present-day conditions, but transferred to SRES A1B conditions for 2050 (see text for details) • albopictus_a2.tif – Ecological niche model for Aedes albopictus calibrated under present-day conditions, but transferred to SRES A2 conditions for 2050 (see text for details) • albopictus_b1.tif – Ecological niche model for Aedes aegypti calibrated under present-day conditions, but transferred to SRES B1 conditions for 2050 (see text for details

Inferring distributional shifts of epidemiologically important North and Central American sandflies from Pleistocene to future scenarios

Nine sandfly species (Diptera: Psychodidae) are suspected or proven vectors of Leishmania spp. in the North and Central America region. The ecological niches for these nine species were modelled in three time periods and the overlaps for all time periods of the geographic predictions (G space), and of ecological dimensions using pairwise comparisons of equivalent niches (E space), were calculated. Two Nearctic, six Neotropical and one species in both bioregions occupied a reduced number of distribution areas. The ecological niche projections for most sandfly species other than Lutzomyia shannoni and Lutzomyia ovallesi have not expanded significantly since the Pleistocene. Only three species increase significantly to 2050, whereas all others remain stable. Lutzomyia longipalpis shared a similar ecological niche with more species than any other, although both L. longipalpis and Lutzomyia olmeca olmeca had conserved distributions over time. Climate change, at both regional and local levels, will play a significant role in the temporal and spatial distributions of sandfly species.Fil: Moo Llanes, David A.. Universidad Nacional Autónoma de México; MéxicoFil: Pech May, Angélica del Rosario. Ministerio de Salud. Instituto Nacional de Medicina Tropical; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; ArgentinaFil: Ibarra Cerdeña, C. N.. Cinvestav Unidad Merida; México. Universidad Nacional Autónoma de México; MéxicoFil: Rebollar Téllez, E. A.. Universidad Autónoma de Nuevo León; MéxicoFil: Ramsey, Janine. Instituto Nacional de Salud Pública/crisp; Méxic

Assessing the Potential Distributions of the Invasive Mosquito Vector Aedes albopictus and Its Natural Wolbachia Infections in México

The Asian tiger mosquito Aedes albopictus is currently the most invasive vector species, with a widespread global distribution. Aedes albopictus is the potential vector of diverse arboviruses, including Zika and dengue. This study updated the ecological niche model of Ae. albopictus and inferred the potential distribution of natural Wolbachia infections in Ae. albopictus in México. The ecological niche models were constructed based on diverse model settings to better estimate the potential distributions and uncertainty indices of both Ae. albopictus and its natural Wolbachia infections in México. The distribution of Ae. albopictus covered the states across Northern México, the Gulf of México, the Pacific Coast of México, Central México, and the southeast of México. The ecological niche model of the natural Wolbachia infections in Ae. albopictus populations anticipated the occurrence of natural Wolbachia infections in the southeast of México, the Chiapas border with Guatemala, and Veracruz. These results can be used to prioritize vector surveillance and control programs in México for strategic and future decision-making; however, it is still necessary to establish active surveillance programs to assess model predictions based on the independent sampling of Ae. albopictus from different invasion zones in México. Finally, vector surveillance should also screen the natural Wolbachia infections in Ae. albopictus to validate Wolbachia predictions across México, particularly in the southeast of México

Niche divergence and paleo-distributions of Lutzomyia longipalpis mitochondrial haplogroups (diptera: psychodidae)

Lutzomyia longipalpis is a complex of species which has a wide but discontinuous distribution from southeastern Mexico to northern Argentina and Uruguay. To date, eight mitochondrial haplogroups have been identified along its distribution although key environmental tolerances and ecological niche models have been analyzed only at the complex level. The aim of the present study was to analyze whether genetic diversification using three mitochondrial genes of the Lu. longipalpis complex is associated with niche divergence and to explore evolution of distributional projections of all haplogroups between the Last Glacial Maximum (LGM; 21,000 yrs ago) and the present. Current occurrence of all haplogroups was used to develop ecological niche models (ENM) and these were projected in both periods to quantify and identify geographic area shifts. Environmental space was used to estimate niche similarity between major clades and pairwise between individual haplogroups. The two major Lu. longipalpis clades (Mex, CA, Col and Ven vs Arg and Bra) had significantly different environmental space, indicating niche divergence. Environmental space overlap of southern haplogroups was variable, with divergent niche, except between Arg and ArgBra. The most suitable regions for the ArgBra haplogroup were northeastern and southeastern Brazil, and the Gran Chaco region. In contrast, ENM of haplogroups within the northern major clade have significantly similar niche, with highest geographic ENM suitability along both the Caribbean and Pacific coasts. The intensity and coverage of high suitability areas in the LGM decreased for most haplogroups in the present. Integrating ENM and phylogenetic analyses has allowed us to test hypotheses of niche similarity between Lu. longipalpis haplogroups and major clades, and to identify conserved distributional areas of haplogroups since the LGM, with the exception of Arg. Evidence for distributional shifts and overlap of haplogroups is important to analyze Leishmaniasis´ eco-epidemiology and to successfully monitor and control transmission.Fil: Moo Llanes, David A.. Instituto Nacional de Salud Pública. Centro Regional de Investigación en Salud Pública; MéxicoFil: Pech May, Angélica del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Instituto Nacional de Salud Pública. Centro Regional de Investigación en Salud Pública; México. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Medicina Tropical.; ArgentinaFil: Montes de Oca Aguilar, Ana Celia. Instituto Politécnico Nacional. Centro de Investigación y de Estudios Avanzados; MéxicoFil: Salomón, Oscar Daniel. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Medicina Tropical.; Argentina. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Ramsey, Janine. Instituto Nacional de Salud Pública. Centro Regional de Investigación en Salud Pública; Méxic

Use of Unmanned Aerial Vehicles for Building a House Risk Index of Mosquito-Borne Viral Diseases

The Vector Control Program in Mexico has developed operational research strategies to identify entomological and sociodemographic parameters associated with dengue transmission in order to direct targeted actions and reduce transmission. However, these strategies have limitations in establishing their relationship with landscape analysis and dengue transmission. This study provides a proof of concept of the use of unmanned aerial vehicle technology as a possible way to collect spatial information of the landscape in real time through multispectral images for the generation of a multivariate predictive model that allows for the establishment of a risk index relating sociodemographic variables with the presence of the vector in its different larval, pupal, and adult stages. With flight times of less than 30 min, RGB orthomosaics were built, where houses, roads, highways, rivers, and trails are observed in detail, as well as in areas with a strong influence of vegetation, detailing the location of the roofs or the infrastructure of the house, grass, bushes, and trees of different dimensions, with a pixel resolution level of 5 centimeters. For the risk index, we developed a methodology based on partial least squares (PLS), which takes into account the different type of variables are involved and the geographic distribution of the houses as well. Results show the spatial pattern of downtown low-risk housing, which increases as we approach the outskirts of the town. The predictive model of dengue transmission risk developed through orthomosaics can help decision makers to plan control and public health activities

Comparison of Climate Change Scenarios of <i>Rhipicephalus sanguineus</i> sensu lato (Latreille 1806) from México and the Boarders with Central America and the United States

In America, the presence of Rhipicephalus sanguineus sensu stricto and Rhipicephalus linnaei has been confirmed. Both species are found in sympatry in the southern United States, northern Mexico, southern Brazil, and Argentina. The objective of this work is to evaluate the projection of the potential distribution of the ecological niche of Rhipicephalus sanguineus sensu lato in two climate change scenarios in Mexico and the border with Central America and the United States. Initially, a database of personal collections of the authors, GBIF, Institute of Epidemiological Diagnosis and Reference, and scientific articles was built. The ENMs were projected for the current period and two future scenarios: RCP and SSP used for the kuenm R package, the ecological niche of R. sanguineus s.l. It is distributed throughout the Mexico and Texas (United States), along with the border areas between Central America, Mexico, and the United States. Finally, it is observed that the ecological niche of R. sanguineus s.l. in the current period coincides in three degrees with the routes of human migration. Based on this information, and mainly on the flow of migrants from Central America to the United States, the risk of a greater gene flow in this area increases, so the risk relating to this border is a latent point that must be analyzed