Spatial Distribution of Phlebotominae in Puerto Iguazu-Misiones, Argentina-Brazil-Paraguay Border Area

Abstract

SUMMARY The first Argentinian autochthonous human case of visceral leishmaniasis (VL) was confirmed in Posadas (Misiones) in 2006. Since then, the disease has increased its incidence and geographical distribution. In the 2006-2012 period, 107 human cases were detected (11 deaths). The presence of Lutzomyia longipalpis was detected in peridomiciles in Puerto Iguazú urban area in 2010; some of these findings were associated with households where cases of canine VL had already been reported. The objective of this study was to ascertain the abundance and spatial distribution of Lu. longipalpis in Puerto Iguazú City, on the Argentina-Brazil-Paraguay border. Lu. longipalpis proved to be exclusively urban and was found in 31% of the households sampled (n = 53), 67% of which belonged to areas of low abundance, 20% to areas of moderate abundance and 13% to areas of high abundance. Nyssomyia whitmani was the only species found both in urban and peri-urban environments, and Migonemyia migonei was registered only on the outskirts of the city. Due to the fact that Puerto Iguazú is considered to be at moderate risk at the moment, it is necessary to intensify human and canine case controls, as well as take integrated prevention and control measures regarding the environment, vectors and reservoirs on the Argentina-Brazil-Paraguay border area.

Co‐occurrence and seasonal and environmental distributions of the sandflies Lutzomyia longipalpis and Nyssomyia whitmani in the city of Puerto Iguazú, northeastern Argentina

“…whitmani indicate that TL cases could appear throughout the warm season. As has been previously reported, this species was observed mainly in peri‐urban and more rural areas (Souza et al ., ; Fernández et al ., ; Santini et al ., ). Only a few sites with a high abundance of Ny.…”

“…Regarding the distribution in space, the peridomicile farthest away from the forest edge had the highest proportion of Lu. longipalpis , as was found previously (Santini et al ., ; de Andrade et al ., ). In addition, in this study we found that urbanized landscapes or areas with more public urban services were more suitable for Lu.…”

“…The city of Puerto Iguazú was divided into 51 squares of 400 by 400 m. In each square, one household peridomicile (sample site) was selected using the ‘worst scenario’ criterion (Santini et al , ). The ‘worst scenario’ is a functional definition to denote a site within the study patch with the greatest probability of Phlebotominae presence as a consequence of habitat conditions, such as the presence of dense vegetation which provides shadow, humidity and detritus; soil rich in organic material, and access to blood sources, without the interference of external light.…”

“…longipalpis has adapted to be an urban or peri‐urban species, but in some places it is still found in rural environments (Salomón et al ., ). Nyssomyia whitmani is a species found mainly in rural areas and it is also common in areas with primary or secondary vegetation (Souza et al ., ; Rangel & Lainson, ; Salomón et al ., ; Santini et al ., ), with probable trends towards urban adaptation (Rangel & Lainson, ; Santini et al ., ).…”

Phlebotominae in peri‐domestic and forest environments inhabited by Alouatta caraya in northeastern Argentina

“…Nyssomyia neivai and Ny. whitmani were found with Leishmania DNA in the country (Córdoba‐Lanús et al ., ; Salomón et al ., ), whereas Mg. migonei could be the link between zoonotic and anthropozoonotic cycles (Santini et al ., ). Many mammals (e.g.…”