Door-to-door screening as a strategy for the detection of congenital Chagas disease in rural Bolivia

Abstract

Objective: To demonstrate the feasibility of a house-to-house screening system used for congenital Chagas disease in rural areas based on an active search for pregnant women and newborns in their homes in addition to passive case detection in health facilities.

Methods: Exploratory phase conducted by the research team followed by an operational period coordinated by municipal health service. A blood sample was taken for serological and parasitological tests of Trypanosoma cruzi from pregnant women who were searching antenatal care or visited at home by field investigators. Infants born to T. cruzi-infected women were examined for infection at birth and again at 1 and 7 months of age.

Results: 64.5% of the pregnant women were infected. Congenital infection was diagnosed at birth in 4.0% (12/299) of the children born to seroreactive mothers. Twelve additional cases of infection (4%) were diagnosed in children between 1 and 7 months of age. Finally, 37% of the children were lost to follow-up in the exploratory phase and 53% during the operational phase (P=0.002), significantly fewer than in most passive case detection studies.

Conclusion: Despite poorer outcomes after door-to-door screening activities have been transferred to the health system, a combined strategy based on active and passive case detection appeared to be efficient for identifying rural cases of congenital Chagas disease.