Metagenomic Analysis of Taxa Associated with Lutzomyia longipalpis, Vector of Visceral Leishmaniasis, Using an Unbiased High-Throughput Approach

CHRISTINA MC CARTHY; L. DIAMBRA; R. RIVERA-POMAR

PLOS NEGLECTED TROPICAL DISEASES

PUBLIC LIBRARY SCIENCE

Año: 2011 vol. 5 p. 1304 - 1304

1935-2735

Background: Leishmaniasis is one of the most diverse and complex of all vector-borne diseases worldwide. It is caused byparasites of the genus Leishmania, obligate intramacrophage protists characterised by diversity and complexity. Its mostsevere form is visceral leishmaniasis (VL), a systemic disease that is fatal if left untreated. In Latin America VL is caused byLeishmania infantum chagasi and transmitted by Lutzomyia longipalpis. This phlebotomine sandfly is only found in the NewWorld, from Mexico to Argentina. In South America, migration and urbanisation have largely contributed to the increase ofVL as a public health problem. Moreover, the first VL outbreak was recently reported in Argentina, which has already caused7 deaths and 83 reported cases.Methodology/Principal Findings: An inventory of the microbiota associated with insect vectors, especially of wildspecimens, would aid in the development of novel strategies for controlling insect vectors. Given the recent VL outbreak inArgentina and the compelling need to develop appropriate control strategies, this study focused on wild male and femaleLu. longipalpis from an Argentine endemic (Posadas, Misiones) and a Brazilian non-endemic (Lapinha Cave, Minas Gerais) VLlocation. Previous studies on wild and laboratory reared female Lu. longipalpis have described gut bacteria using standardbacteriological methods. In this study, total RNA was extracted from the insects and submitted to high-throughputpyrosequencing. The analysis revealed the presence of sequences from bacteria, fungi, protist parasites, plants andmetazoans.Conclusions/Significance: This is the first time an unbiased and comprehensive metagenomic approach has been used tosurvey taxa associated with an infectious disease vector. The identification of gregarines suggested they are a possibleefficient control method under natural conditions. Ongoing studies are determining the significance of the associated taxafound in this study in a greater number of adult male and female Lu. longipalpis samples from endemic and non-endemiclocations. A particular emphasis is being given to those species involved in the biological control of this vector and to theetiologic agents of animal and plant diseases.