6 research outputs found
First Detection of Leishmania major DNA in Sergentomyia (Spelaeomyia) darlingi from Cutaneous Leishmaniasis Foci in Mali
Leishmania major complex is the main causative agent of zoonotic cutaneous leishmaniasis (ZCL) in the Old World. Phlebotomus papatasi and Phlebotomus duboscqi are recognized vectors of L. major complex in Northern and Southern Sahara, respectively. In Mali, ZCL due to L. major is an emerging public health problem, with several cases reported from different parts of the country. The main objective of the present study was to identify the vectors of Leishmania major in the Bandiagara area, in Mali. Methodology/Principal Findings: An entomological survey was carried out in the ZCL foci of Bandiagara area. Sandflies were collected using CDC miniature light traps and sticky papers. In the field, live female Phlebotomine sandflies were identified and examined for the presence of promastigotes. The remaining sandflies were identified morphologically and tested for Leishmania by PCR in the ITS2 gene. The source of blood meal of the engorged females was determined using the cyt-b sequence. Out of the 3,259 collected sandflies, 1,324 were identified morphologically, and consisted of 20 species, of which four belonged to the genus Phlebotomus and 16 to the genus Sergentomyia. Leishmania major DNA was detected by PCR in 7 of the 446 females (1.6%), specifically 2 out of 115 Phlebotomus duboscqi specimens, and 5 from 198 Sergentomyia darlingi specimens. Human DNA was detected in one blood-fed female S. darlingi positive for L. major DNA. Conclusion: Our data suggest the possible involvement of P. duboscqi and potentially S. darlingi in the transmission of ZCL in Mali
Contribution de la biologie moleculaire Ă l Ă©tude des vecteurs de la leishmaniose (A propos de deux Ă©tudes : Bandiagara (Mali) et Kabylie (Algerie) )
Les leishmanioses sont des affections parasitaires cutanées et/ou viscérales dues à des protozoaires Flagellés du genre Leishmania. Elles sont transmises à l homme par la piqûre des phlébotomes (Diptera: Psychodidae) appartenant aux genres Phlebotomus (Ancien Monde) et Lutzomyia (Nouveau Monde). L identification des vecteurs et des hôtes réservoirs joue un rôle clé dans les études épidémiologiques. Dans ce travail, nous nous sommes intéressés à l identification des vecteurs de Leishmania dans deux foyers distincts, le foyer endémique de leishmaniose viscérale à L. infantum en Kabylie (Algérie) et le foyer de leishmaniose cutanée zoonotique à L. major à Bandiagara (Mali). Les phlébotomes capturés dans les deux foyers sont morphologiquement identifiés et les femelles suspectées infectées sont disséquées et examinées à frais sous loupe binoculaire et microscope à la recherche de promastigotes, puis analysées moléculairement par séquençage direct d un fragment de la séquence du gène ITS2. P. (P.) duboscqi, Sergentomyia (S.) darlingi et P. (L.) longicuspis femelles ont été trouvées infectées avec de l ADN de L. major à Bandiagara et de l ADN de L. infantum en Kabylie. De plus, l ADN de sang humain est amplifiée à partir de S. darlingi trouvée infectée avec de l ADN de L. major. Ces observations viennent s ajouter aux données de la littérature sur le rôle vecteur des espèces de phlébotomes identifiées et permettent d incriminer de nouvelles espèces dans la transmission des leishmanioses, notamment S. darlingi, jamais incriminée jusque-là . L apport de la biologie moléculaire dans l identification des vecteurs de leishmaniose est discuté.Leishmaniases are diseases that range in severity from skin lesions to fatal systemic infection, caused by flagellate protozoa of the genus Leishmania. They are transmitted to humans by the bite of sandflies (Diptera: Psychodidae) of the genera Phlebotomus (Old World) and Lutzomyia (New World). Identification of vectors and reservoir hosts are more important in epidemiological studies. The aim of the present study was to identify the vectors of leishmaniasis in two endemic focuses, (i) zoonotic cutaneous leishmaniaisis focus due to Leishmania major in Bandiagara (Mali) and (ii) cutaneous and visceral leishmaniasis focus caused by Leishmania infantum in Kabylia (Algeria). Sandflies collected from the both focuses were morphologically identified; the females alive were examined for research the promastigotes. The remaining of sandfly females were morphologically identified and tested by direct sequencing of a fragment of Leishmania ITS2 sequence. P. (Phlebotomus) duboscqi, Sergentomyia (Spelaeomyia) darlingi and P. (Larroussius) longicuspis females were found infected with the DNA of L. major in Bandiagara and L. infantum in Kabylia respectively. In addition, human DNA was amplified in S. (Spelaeomyia) darlingi found infected with L. major DNA. Our observations added to the literature data on the role vector of sandfly species proved and those incriminated in the transmission of leishmaniasis, particularly S. darlingi which has never been suspected so far. The contribution of the molecular biology to identify the leishmaniasis vectors is discussed.PARIS13-BU Sciences (930792102) / SudocSudocFranceF
Dendrogram constructed using sequences of <i>Leishmania major</i> from <i>S. darling</i> (HQ591339) and <i>P. duboscqi</i> (HQ591340).
<p>ITS2 polymerase chain reaction (PCR) fragment of the sequences amplified were aligned with the reference strains (<i>L. major</i>, <i>L. tropica</i>, <i>L. infantum</i>, <i>L. donovani</i>, <i>L. mexicana</i>, <i>L. chagasi</i> and <i>L. guyanensis</i>) and tree constructed using NJ. Bootstrap analysis was performed with 1000 replicates and <i>P</i> values reported at nodes.</p
<i>Leishmania</i> ITS2 PCR products from collected female sandflies.
<p><i>Leishmania</i> DNA amplified within <i>S darlingi</i> (1 to 5) and <i>P. duboscqi</i> (6–7). N = negative control, band size of the PCR product is 400 bp.</p
Distribution of sandflies in the Bandiagara area.
<p>Distribution of sandflies in the Bandiagara area.</p