Leishmania (L.) mexicana infected bats in Mexico: novel potential reservoirs

PLoS Negl Trop Dis. 2015 Jan 28;9(1):e0003438. doi: 10.1371/journal.pntd.0003438. eCollection 2015 Jan.

Abstract

Leishmania (Leishmania) mexicana causes cutaneous leishmaniasis, an endemic zoonosis affecting a growing number of patients in the southeastern states of Mexico. Some foci are found in shade-grown cocoa and coffee plantations, or near perennial forests that provide rich breeding grounds for the sand fly vectors, but also harbor a variety of bat species that live off the abundant fruits provided by these shade-giving trees. The close proximity between sand flies and bats makes their interaction feasible, yet bats infected with Leishmania (L.) mexicana have not been reported. Here we analyzed 420 bats from six states of Mexico that had reported patients with leishmaniasis. Tissues of bats, including skin, heart, liver and/or spleen were screened by PCR for Leishmania (L.) mexicana DNA. We found that 41 bats (9.77%), belonging to 13 species, showed positive PCR results in various tissues. The infected tissues showed no evidence of macroscopic lesions. Of the infected bats, 12 species were frugivorous, insectivorous or nectarivorous, and only one species was sanguivorous (Desmodus rotundus), and most of them belonged to the family Phyllostomidae. The eco-region where most of the infected bats were caught is the Gulf Coastal Plain of Chiapas and Tabasco. Through experimental infections of two Tadarida brasiliensis bats in captivity, we show that this species can harbor viable, infective Leishmania (L.) mexicana parasites that are capable of infecting BALB/c mice. We conclude that various species of bats belonging to the family Phyllostomidae are possible reservoir hosts for Leishmania (L.) mexicana, if it can be shown that such bats are infective for the sand fly vector. Further studies are needed to determine how these bats become infected, how long the parasite remains viable inside these potential hosts and whether they are infective to sand flies to fully evaluate their impact on disease epidemiology.

MeSH terms

  • Animals
  • Chiroptera / parasitology*
  • DNA, Protozoan / analysis
  • Disease Reservoirs*
  • Female
  • Humans
  • Leishmania mexicana / genetics
  • Leishmaniasis, Cutaneous / transmission*
  • Male
  • Mexico / epidemiology
  • Mice
  • Mice, Inbred BALB C

Substances

  • DNA, Protozoan

Grants and funding

This work was funded by the Universidad Nacional Autónoma de México (PAPIIT IN215212 to IB, IN 202711, IN 209314 to VSC). Funding was also obtained from Consejo Nacional de Ciencia y Tecnología (CONACyT) 132811 to VSC and from Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México to CRS, and CONACyT-FOSSIS 69530. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.