Detection of natural infection of Lutzomyia cortelezzii with Leishmania braziliensis by Polymerase Chain Reaction (PCR) in Chaco, Argentina.

ROSA JR; BRAZIL R; PITA PEREIRA D; SZELAG EA; SALOMON OD

Kusadasi

Simposio; 7th International Symposium on Phlebotomine Sand flies; 2011

American Cutaneous Leishmaniasis in Argentina is associated mainly with Leishmania braziliensis, but also with L. amazonensis and L. guyanensis, while L. infantum has been isolated from visceral leishmaniasis cases. Lutzomyia neivai and Lu. whitmani have been found naturally infected with L. braziliensis, and Lu. longipalpis with L. infantum. However, in the western Chaco biogeographical region (Dry Chaco), which is an endemic area of mucocutaneous leishmaniasis, there are no reports of naturally infected phlebotomines. Thus, in order to look for infected sand flies, traps were located from November 2006 to December 2007 in the city of Misión Nueva Pompeya, at two stations with human cases: Los Pozos (24º54´28˝S, 61°22´05˝W) and Fortín Arenales (24º58´12˝S, 61º21´32W). Captures were performed monthly using CDC light traps from 19:00 to 07:00 in domicile (inside houses), peridomicile (10 m from houses in animal dwellingspoultry/ cattle/goats/horses) and in the forest (90 to 110 m from the house). The Phlebotominae captured were separated by gender, and females were killed at 0°C and the species identified, and stored by species at -20°C in pools of 10 Phlebotominae for genera specific PCR + species-specific Dot-blot. A total of 1702 sand flies were captured and identified: Lutzomyia migonei (83.8%), Lu. cortelezzi females complex (5.8%), Lu. sallesi males (4.3%), Lu. peresi (3.3%), Lu. quinquefer (1.2%), Lu. cortelezzii males (1.1%), Lu. torresi (0.2%) and Lu. neivai (0.2%). No significant differences were found in species diversity or abundance between both sites studied. A total of 80 Phlebotominae females were analyzed by PCR: Lu. cortelezzii: 50 (Los Pozos: 10; Fortín Arenales: 40) and Lu. migonei: 30 (Los Pozos: 20; Fortín Arenales: 10). Two pools of Lu. cortelezzii from the forest of Fortin Arenales were positive by PCR and Dot-blot for L. (V) braziliensis infection. Further studies of vectorial competence are required to incriminate Lu. cortelezzii as vector of L. (V) braziliensis in the Chaco region.