The first record of Lutzomyia longipalpis in the Argentine northwest

online | memorias.ioc.fiocruz.br The urban presence of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Salomón & Orellano 2005) was first recorded in Argentina in Formosa province in 2004; it was associated with an outbreak of visceral leishmaniasis (VL) in the neighbouring city of Asunción, Paraguay Republic. In 2006, in Posadas, which is located in Misiones province (also on the Paraguay border), the first autochthonous case of urban human VL with the presence of Lu. longipalpis was recorded, along with some canine VL cases (Salomón et al. 2008b). Subsequently, the vector began spreading throughout the northeast region of Argentina and eventually reached Puerto Iguazú (on the border with Brazil and Paraguay) before moving toward the south to Corrientes, Entre Ríos and Chaco provinces (Salomón et al. 2009, 2011a, b) and to Artigas and Salto departments, Uruguay (Salomón et al. 2011a). The spread encompassed the ecoregions of humid Chaco, Paraná forest and spinal vegetation (Burkart et al. 1999). From 2006-2012, 103 cases of human VL were confirmed, with the highest incidence reported in Misiones province (Gould et al. 2013). In Santiago del Estero province, from 2007 to the present date, six VL cases were recorded, with Migonemyia migonei (Franςa, 1920) present as the putative vector in the Chaco region (Salomón et al. 2010). Thus far, three VL cases in Salta province have been reported to the Health Surveillance National System, Ministry of Health of the Nation (Gould et al. 2013). To study one of these cases, Barrio et al. (2012) used an epidemiological survey to identify an area with the ecological characteristics of Dry Chaco (located 70 km from the study area of the present work) as the likely location of human infection, without any reports of entomological captures associated with the case. In the present paper, the results of captures performed during the first half of 2013 are presented to determine the species of sandflies that are present in Tartagal city, an area that corresponds to a transition between the “Yungas” jungle foothills and Dry Chaco. Tartagal city (22o31’00’’S 63o47’35’’O) is located in General José de San Martín department, to the northeast of Salta province, 360 km from the capital city, 55 km south of the international limit with Bolivia and at least 100 km away from the VL case recorded in 2009 (A, B in Figure). To determine the presence of Phlebotominae, 30 CDC-type light traps (Sudia & Chamberlain 1998) were used in each season. Trapping was simultaneously performed at 10 different sites for at least two consecutive nights in each place, with at least 400 m between each site (C in Figure). From April-May, site 8 was not sampled and a new site was included (8N). Samplings were performed in 2013 between January 28-30 (2 consecutive days) and between April 29-May 2 (3 consecutive days), corresponding to the summer and fall seasons, respectively. The average temperature was 22oC at minimum and 42oC at maximum during the summer sampling and 21oC at minimum and 29oC at maximum during the autumn sampling. The sites were selected using the “worst scenario” criterion (e.g., the presence of animals, associated vegetation and shade) (Feliciangeli et al. 2006, Correa Antonialli et al. 2007). The captured Phlebotominae were identified following the Galati key (Galati 2003). The most abundant species in both samplings was Lu. longipalpis. A total of 277 Phlebotominae were captured. They corresponded to the following species (listed from most to least abundant): Lu. longipalpis (63%), Mg. migonei (22%), Evandromyia cortelezzisallesi complex (11%, the females in both species are indistinguishable) and Nyssomyia neivai (4%). The overall female/male ratio for Lu. longipalpis was 0.3 doi: 10.1590/0074-0276130358 Financial support: FMS All authors belong to Red de Investigación de Leishmaniasis en la Argentina, Buenos Aires, Argentina + Corresponding author: [email protected] Received 11 July 2013 Accepted 4 October 2013 The first record of Lutzomyia longipalpis in the Argentine northwest