Epidemiology of Chagas disease in Andrés Eloy Blanco, Lara, Venezuela: Triatomine infestation and human seroprevalence

Abstract

A seroepidemiological survey and vector captures were performed in four rural communities in Andrés Eloy Blanco, Lara State, Venezuela. Systematic random sampling was based on family clusters, with samples drawn from 869 individuals to determine anti-Trypanosoma cruzi and anti-Leishmania sp. antibodies by indirect immunofluorescence. Positive individuals were defined as ≥ 1:32 for anti-T. cruzi antibody and non-reactive to Leishmania sp. antigen, revealing an antibody frequency of 6.9% (n = 60), of whom 46.66% were females and 53.33% males and 60% were over 39 years of age. Some 5 (8.33%) seropositive individuals were under 10 years of age and 10 (16.66%) under 20 years. Rhodnius prolixus and Panstrongylus geniculatus were the triatomines captured, with infestation rates of 1.9% and 10.54%, colonization index of 0% and 18.18% in infested houses, and a T. cruzi infection index of 20% and 5.07%, respectively. The results suggest active Chagas disease transmission in Andrés Eloy Blanco in the last two decades and that P. geniculatus is replacing R. prolixus as the Chagas disease vector.