A new study has revealed that it would be possible to diagnose and treat Chagas disease in children in low-resource settings with the help of a new targeted screening strategy.
Chagas disease is caused by a single-cell parasite called Trypanosoma cruzi, which is transmitted by triatomine bugs that infest houses in poor communities.
This disease infects an estimated 11 million people in Latin America and is much more fatal than any other parasitic disease in the Americas.
The traditional control programs for this disease have not been successful, as they were targeted more towards disrupting the transmission of T. cruzi through vector control measures (such as insecticide spraying), instead of going for active case detection and specific treatment of infected people.
Though the control actions have reduced the geographic range and prevalence of major triatomine vectors, timely diagnosis of already infected patients has been ignored, which may not result in the effective treatment of the disease.
Another important reason for the low rates of treatment is that health services and control programs in Latin America are short of sufficient resources for full blood screening and organized treatment in the most affected areas.
The study, by Michael Levy from the Emory University and the Centers for Disease Control and Prevention, Atlanta, USA, currently at the Fogarty International Center of the NIH, and colleagues, has come up with an alternative screening strategy that is likely to be more efficient and cost-effective, and hence much more viable in the resource-poor regions afflicted by the disease.
A serological survey was performed in children aged between 2-18 years and living in a peri-urban community of Arequipa, Peru, where a vector control campaign is under way for disrupting T. cruzi transmission.
The researchers found that 5.3 per cent of children were already infected much before their households received insecticide application. It was also found that households with infected children were considerably crowded.
The researchers' findings were then related to data that had been collected during the vector control campaign (entomological, spatial, and census data).
It was found that using such data in order to target diagnostic testing would have resulted in identifying over 83 per cent of the infected children while testing only 22 per cent of eligible children.
The researchers came to a conclusion that the data, which was easily collected during a constant insecticide spraying campaign in Arequipa, could be used to identify children at greatest risk of infection with T. cruzi.
According to the authors, the study is the first to describe T. cruzi transmission in an urban environment and to show evidence proving that the transmission may be epidemic in Arequipa.
The study was published in the open-access journal PLoS Neglected Tropical Diseases.