Molecular typing of Trypanosoma cruzi strains infecting Triatoma infestans, domestic dogs and cats from a rural area of northwestern Argentina.

CARDINAL MV; LAURICELLA MA; MARCET PL; LEVIN JM; KITRON U; GÜRTLER RE; SCHIJMAN AG

Washington, EEUU.

Congreso; 54th Annual Meeting of the American Society of Tropical Medicine and Hygiene.; 2005

American Society of Tropical Medicine and Hygiene

As part of a comprehensive study aimed at modeling the transmission dynamics of Trypanosoma cruzi in a rural area in NW Argentina, the T. cruzi strains infecting Triatoma infestans, domestic dogs and cats from two areas with different history of vector control and surveillance were cultured and typified to the sublineage level by PCR strategies targeted to spliced-leader DNA, 18s rDNA, 24s alfa rDNA and A10 genomic markers. Overall, T. cruzi II (TCII) was the predominant lineage (93%) among 70 stocks typified, followed by lineage I (TCI) in 4%. TCII was found in 36 (92%) T. infestans, 25 (93%) domestic dogs and in all of the cats (N=4). TCI was found in 2 T. infestans and 1 dog. Notably, one dog and one T. infestans had a mixed infection with both lineages. In stocks belonging to domestic and peridomestic T. infestans, T. cruzi IIe (TCIIe) was the predominant sublineage found (61%), followed by T. cruzi IIb/e in 18%; TCI in 5%. T. cruzi IIc (TCIIc), T. cruzi IId (TCIId) and a mixed infection of TCI and TCIIe were found in one insect each. Among 25 dogs, TCIIe was found in 81% of stocks, TCIIc in 11%, TCI in 4% (1 dog) and in one dog TCI was found together with TCIIe. All four cats were infected with TCIIe. Significant differences in T. cruzi prevalence rates in T. infestans and dogs were registered between the two areas with different history of vector control and surveillance. However, both areas shared all T. cruzi sublineages except for, TCIId that was only found in the area under sporadic control actions.