Evaluating the spatial distribution of Leishmania parasites in Colombia from clinical samples and human isolates (1999 to 2016)

Abstract

In Colombia, nine species of parasites of the genus Leishmania circulate in more than 20 sand fly species, putting at risk of contracting the disease approximately 60% of the population. The Federico Lleras Acosta Dermatological Center, a reference center in Colombia, has been treating patients with cutaneous and mucosal leishmaniasis for more than 15 years, identifying the infecting Leishmania species from different clinical samples, and recording systematically all the epidemiological and geographic information related to each diagnosed patient. With this valuable information, the objective of this work was to perform a long term and large-scale study, aiming to identify the Leishmania species circulating in Colombia from clinical samples from 1999 to 2016, and to assess their current and potential spatial distribution. In all, four Leishmania species were identified in 688 samples from 183 municipalities distributed in 28 of the 32 departments of the country, and 387 records were georeferenced, from 20 departments. The most widespread species was L . (V . ) braziliensis , showing new collection records, and the species related to areas with highest leishmaniasis transmission was L . (V . ) panamensis . Ecological niche models were built for the three species that had more than 20 georeferenced records, showing a potential distribution for L . (V . ) braziliensis on 42% of the national territory mainly in the interandean valleys, and the Orinoquia and Amazon regions. Leishmania (V . ) guyanensis potential distribution covers 36% of Colombia continental territory with a spatial distribution similar to that of L . (V . ) braziliensis . There was a marked tendency of L . (V . ) panamensis to be distributed in the northwest of the country occupying 35% of the national area and mainly in areas of transformed ecosystems. Species were identified in patients from areas where the occurrence of cases was unprecedented, which suggests that the distribution of Leishmania may be greater than currently known. To improve the predictive capacity of the models, we suggest incorporating, in future studies, Leishmania samples from vectors and reservoirs that have a greater dependence on environmental variables. Our results are an important tool for health systems because they allow potential areas of transmission and information gaps to be identified.

Complex ecological interactions across a focus of cutaneous leishmaniasis in Eastern Colombia: novel description of Leishmania species, hosts and phlebotomine fauna

“…Previous reports of CL outbreaks in Colombia have described higher frequencies of L . panamensis than L. braziliensis , with the latter mainly found in sylvatic environments [ 12 , 52 – 55 ]. As was found in previous studies, we observed a greater genetic diversity in L. braziliensis than in L. panamensis [ 9 , 12 ].…”

“…ovallesi (63% L. braziliensis and 73% L. panamensis ) and Lu. gomezi (52% L. braziliensis and 66% L. panamensis ) [ 55 ]. Colombian populations of Pi.…”

Genomic Diversification, Structural Plasticity, and Hybridization in Leishmania (Viannia) braziliensis

“…Finally, (iii): migration of animal reservoirs or sand fly vectors responsible for transmission of the parasite within the national territory. L. braziliensis is associated with a wide variety of sand fly vectors (Bejarano et al, 2002;Testa et al, 2002;Ovallos et al, 2013;Ovalle-Bracho et al, 2019).…”

“…Despite these findings, knowledge about the genomic variability of L. braziliensis in other South American regions, such as Colombia, is limited. Different studies describe a high frequency of this species in Colombia; this being more frequent in rural (Perez-Franco et al, 2016;Patino et al, 2017) compared with urban populations (Ramirez et al, 2016;Ovalle-Bracho et al, 2019). In addition, Colombia has a large number of sand fly vectors and animal reservoirs, which are involved in the transmission cycle of the parasite (Valderrama-Ardila et al, 2010;Ferro et al, 2015).…”

Colombian Contributions Fighting Leishmaniasis: A Systematic Review on Antileishmanials Combined with Chemoinformatics Analysis

“…This fact can be considered reasonable due to the fact that L. panamensis is the etiological agent most frequently reported in Colombia [3,6]. However, recent studies reported that L. braziliensis and L. guyanensis have relevant epidemiological reports and wide spatial distribution in Colombia [68,69]. Considering Colombia as a country with a significant number of pathogenic Leishmania species in circulation, these facts are very critical, bearing in mind that parasite sensitivity to antileishmanial agents relies on Leishmania species [70,71].…”