Chagas disease, also known as American trypanosomiasis, is caused by the protozoan parasite Trypanosoma cruzi, and it is endemic in 21 Latin American countries. Due to global migration of infected people, it is also present in non-endemic areas (e.g. Europe, Australia, and Canada). An estimated 6 to 8 million people are infected worldwide.
Chagas disease can be transmitted by several routes. In recent years, chagas disease control campaigns in Latin America have reduced vector transmission, but congenital transmission, passage from an infected mother to her newborn, remains a concern.
Chagas disease can be treated. The younger the patient and the more recent the infection, the more effective the treatment: improving access to diagnosis improves treatment prognosis.
Chagas disease presents itself in 2 phases:
- The acute phase, which lasts for approximately two months following infection and often goes undiagnosed. Amongst children approximately 10 per cent of acute infections are fatal.
- The chronic phase, during which parasites migrate to the heart and digestive muscles, lasts an indeterminate amount of time and patients can be largely asymptomatic. Eventually, organ damage manifests in cardiac and digestive disorders in 10 to 30% of patients. Most frequently, deterioration of these organs causes death.
The diagnostic landscape
Access to information, diagnostics, and treatment is a major challenge in Chagas disease endemic regions. There is a need for reinforcement of national control initiatives and strengthening diagnostic capacities for acute, chronic and congenital Chagas disease.
Microscopy remains the test of reference to diagnose acute and congenital Chagas disease. Molecular tools (e.g. PCR) are also applied in some countries but their complexity precludes their use in all endemic areas.
In the chronic phase, the number of parasites in the blood is low and direct diagnosis is more difficult. Currently the WHO recommends the combined used of two different serological methods to confirm chronic Chagas disease, as none of the available tests are sensitive enough to be used alone.
To date there are no test for confirming treatment effectiveness. Such markers would be very useful for assessing patients post-treatment and evaluating new drugs in the investigation phase.
FIND's strategic approach
FIND is prioritizing activities in the following areas:
- Supporting development of a molecular test and a point-of-care test for congenital Chagas disease;
- Working with partners to catalyzing the development of a test-of-cure;
- Improving access to diagnostic solutions for Chagas disease, which includes supporting advocacy, driving public policy, and training health care workers.