Molecular epidemiology and ecosystem approach of the reinfestation process by Triatoma infestans in rural communities of the Paraguayan Chaco

ROJAS DE ARIAS ANTONIETA; ANTONIETA ROJAS-DE-ARIAS, MIRIAM ROLON, MARÍA CELESTE VEGA, ANA GÓMEZ, FABIOLA ROMÁN, HUMBERTO SÁNCHEZ, CYNTHIA ACOSTA, CESIA VILLALBA, CECERE MC, ELLEN DOTSON4, PAULA MARCET4.; CELESTE VEGA; ANA GOMEZ; FABIOLA ROMAN; HUMBERTO SANCHEZ; CYNTHIA ACOSTA; CESIA VILLALBA; CECERE MC; MARCELA MARCET; ELLEN DOTSON

BIOMéDICA

INST NACIONAL SALUD

Lugar: Bogotá; Año: 2011 vol. 31 p. 153 - 156

0120-4157

We have found for the first time sylvatic coloniesof T. infestans in the Paraguayan Chaco region. Itis not yet known how widespread these triatominesare: they have been captured at different distancesfrom houses in the communities of 12 de Junio, 10Leguas, and Campo Largo, in ranges from 274 mto over 3 km. The spatial analysis of the distributionand density of triatomines at baseline and theirrelation to the process of house reinfestation andthe distribution of sylvatic triatomines allowed usto infer that in Campo Largo village, two clustersexplain the possible reinfestation process. Thesylvatic clusters close to one of these houses couldexplain the peridomestic and domestic reinfestationof the house.However, since we do not know if the sylvatictriatomines were there prior to insecticide spraying,one possibility is that these populations dispersedinto the wild because of insecticide spraying, atleast the bug populations closest to the community.For the rest of the communities, no significantaggregations were detected, and we can attributereinfestations to flaws in insecticide spraying.Regarding the source of house reinfestation, inlight of the results obtained so far, we can inferthat the reinfesting populations of 12 de Junio aregenetically identical to the baseline population withthe analysis of the CytB gene. Surprisingly, we alsoobserved that sylvatic triatomines collected in thesylvatic habitats near the village also coincidedgenetically with these populations.