Revista da Sociedade Brasileira de Medicina Tropical
Abstract
A seroepidemiological survey was carried out to evaluate Trypanosoma cruzi
infection in an endemic area of the State of Rio Grande do Norte, Brazil, involving rural residents.
Methods: Sixteen municipalities were randomly selected, 15 from the west mesoregion and one
from the central, with an estimated population of 83,852 individuals. A total of 1,950 blood samples
were collected in the west mesoregion and 390 in Caicó. Anti-T. cruzi antibodies were detected
using the Chagatest® ELISA HAI-hemagglutination kits and indirect immunofluorescence.
As sera presented indeterminate results, TESAcruzi® western blot was performed to confirm
reactivity. Results: An estimated seroprevalence of 6.5% was determined for the west mesoregion
and 3.3% for Caicó. Seropositivity rises progressively with the age of individuals, up to 40 years in
Caicó and up to 50 years in the west mesoregion. Only educational level and knowledge regarding
the triatomine were associated with seropositivity. No seroreactive individuals under 18 years
of age were identified. Conclusions: Infection by T. cruzi remains high and is concentrated in
municipalities in the central western area of the west mesoregion; however, evidence suggests a
decline in vector transmission in this mesoregion and in Caicó. Epidemiological variables appear
not to influence seropositivity, with the exception of education and knowledge concerning the
triatomine, among seroreactive individuals from the west mesoregion
