In the favelas and impoverished rural villages of Central and South America, the triatomine bug, known locally as vinchuca, lurks in the walls of many homes.
It approaches its human victims after dark and sucks their blood, transmitting the parasite responsible for Chagas disease.
The disease kills around 10,000 people a year and is incurable if not tackled in the early stages.
However, Spanish scientist Dr Pilar Mateo has developed a slow-release insecticidal paint which is proving remarkably successful in eliminating the triatomine bug, and preventing infections.
In this segment of The Cure, Dr Joff Lacey meets Dr Mateo in a Bolivian village where an estimated 80 percent of residents have Chagas.
And now that all the houses in the community have been painted, the deadly insect has been virtually eliminated.
The insecticidal paint is now also being used to combat dengue fever and malaria in Ghana.
Watch The Cure on Tuesday 22:30; Wednesday 09:30; Thursday 03:30; Friday 16:30; Saturday 22:30; Sunday 09:30; Monday 03:30; Tuesday 16:30 GMT.
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