Incidence of Trypanosoma Cruzi Infection Among Children Following Domestic Reinfestation After Insecticide Spraying in Rural Northwestern Argentina

Abstract

Following increasing reinfestation with Triatoma infestans after insecticide spraying, the household incidence of infection with Trypanosoma cruzi in children was positively related to the domestic abundance of infected T. infestans and the presence or proportion of infected dogs or cats in Amamá, a rural village in northwestern Argentina. Seven (12.1%) children seronegative for antibodies to T. cruzi at baseline, with no history of travel or blood transfusion, seroconverted after three years. Six incident cases lived in houses heavily infested with T. infestans, with high proportions of bugs infected with T. cruzi and having fed on humans or dogs. The remaining incident case occurred under a very light domestic infestation detected only at the endpoint, and most bugs had fed on humans. Dogs had a 17 times greater force of infection than children (4.3% per year). Sustained vector surveillance is crucially needed in high-risk areas for Chagas disease such as the Gran Chaco.

Vectorial capacity of Triatoma guasayana (Wygodzinsky & Abalos) (Hemiptera: Reduviidae) compared with two other species of epidemic importance

“…Results showed that the Health Ministries of Latin-American countries had efficient and economically viable methods for establishing vectorial control and blood transfusion programs which would permit the elimination of some vector species (OMS 2007). However, this was at odds with the recent increase of cases of Chagas disease in the Gran Chaco of Argentina (Gürtler et al 2005).…”

Autonomic Dysfunction and Risk Factors Associated with Trypanosoma cruzi Infection among Children in Arequipa, Peru

“…This finding may reflect lower intensity of parasite exposure, lower parasite burdens, and/or strain differences in Arequipa compared with other study sites. The lower infection prevalence in Arequipa suggests a lower force of infection compared with study sites in Brazil, Argentina, or Bolivia, [33][34][35][36] whereas the relatively flat age prevalence curve supports the hypothesis that the parasite was only introduced into the periurban communities of Arequipa in the early 1990s. 26 Investigators have shown that repeated infection increases cardiac pathology in animal models 37,38 and have suggested that vector control, by decreasing reinfection rates, may be responsible for the milder disease now seen in formerly endemic communities.…”

Molecular epidemiology of domestic and sylvatic Trypanosoma cruzi infection in rural northwestern Argentina

“…Based on molecular evidence, this result lends further support to the importance of dogs and cats as domestic reservoir hosts of T. cruzi given their high infectivity and frequent contact with domestic bugs (Cardinal et al, 2007;Gürtler et al, 2007a, b). Households harboring infected dogs or cats were observed and predicted to be at greater risk of transmission (Cohen and Gürtler, 2001;Gürtler et al, 2005), but molecular evidence of the links between bugs and host species at the household level were lacking. In a similar study in Chaco province, different lineages were found infecting dogs and humans (Diosque et al, 2003).…”

“…We also examined the distribution of T. cruzi lineages among bugs, dogs and cats at a household level. Based on previous evidence (Cardinal et al, , 2007Gürtler et al, 2005Gürtler et al, , 2007a, we hypothesized that domestic Tr. infestans and reservoir hosts from the same house compound would share the same parasite lineages.…”