학술논문

Modelling geospatial distributions of the triatomine vectors of Trypanosoma cruzi in Latin America.
Document Type
Article
Source
PLoS Neglected Tropical Diseases. 8/10/2020, Vol. 14 Issue 8, p1-19. 19p.
Subject
*TRYPANOSOMA cruzi
*POPULATION
*CHAGAS' disease
*SPECIES distribution
*TRIATOMA
*NUMBERS of species
Language
ISSN
1935-2727
Abstract
Approximately 150 triatomine species are suspected to be infected with the Chagas parasite, Trypanosoma cruzi, but they differ in the risk they pose to human populations. The largest risk comes from species that have a domestic life cycle and these species have been targeted by indoor residual spraying campaigns, which have been successful in many locations. It is now important to consider residual transmission that may be linked to persistent populations of dominant vectors, or to secondary or minor vectors. The aim of this project was to define the geographical distributions of the community of triatomine species across the Chagas endemic region. Presence-only data with over 12, 000 observations of triatomine vectors were extracted from a public database and target-group background data were generated to account for sampling bias in the presence data. Geostatistical regression was then applied to estimate species distributions and fine-scale distribution maps were generated for thirty triatomine vector species including those found within one or two countries and species that are more widely distributed from northern Argentina to Guatemala, Bolivia to southern Mexico, and Mexico to the southern United States of America. The results for Rhodnius pictipes, Panstrongylus geniculatus, Triatoma dimidiata, Triatoma gerstaeckeri, and Triatoma infestans are presented in detail, including model predictions and (un)certainty in these predictions, and the model validation results for each of the 30 species are presented in full. The predictive maps for all species are made publicly available so that they can be used to assess the communities of vectors present within different regions of the endemic zone. The maps are presented alongside key indicators for the capacity of each species to transmit T. cruzi to humans. These indicators include infection prevalence, evidence for human blood meals, and colonisation or invasion of homes. A summary of the published evidence for these indicators shows that the majority of the 30 species mapped by this study have the potential to transmit T. cruzi to humans. Author summary: The Pan American Health Organisation's Strategy and Plan of Action for Chagas Disease Prevention, Control and Care highlights the importance of eliminating those triatomine vector species that colonise homes, and has had great success in many locations. Since indoor residual spraying campaigns have targeted these species, their importance relative to other vectors has diminished and their geographical distributions may also have changed. It is now vital to consider the full community of vector species, including previously dominant vectors as well as secondary or minor vector species, in order to target residual transmission to humans. Our aim was to define the geographical distributions of the most commonly reported triatomine species in the Chagas endemic region from northern Argentina and Chile to the southern United States of America. We extracted reports of triatomine vector species observed at specific locations from a public database and we used a geostatistical model to generate fine-scale predictive maps for thirty triatomine vector species. Data quality and data availability issues necessitate careful interpretation of the results, so (un)certainty intervals are presented alongside each map. We also present these maps alongside a summary of the published evidence for key indicators related to the capacity of each species to transmit the Chagas parasite to humans. This evidence shows that most of the 30 species that we have mapped pose a potential threat to human populations. [ABSTRACT FROM AUTHOR]