Chagas disease, or American trypanosomiasis, is a parasitic infection caused by Trypanosoma cruzi parasites. Although the name implicates that cases are confined to the region of the Americas - predominantly Latin America - the disease has spread to other continents as well. About 7 million cases were reported in 2014, but at least 65 million people are at risk, living in endemic areas. The disease is transmitted primarily through the bite of a 'kissing bug' or triatomines, but also from mother to child, through blood transmission, organ transplantation or rarely by oral route. Once the parasites enter the body, they travel via the bloodstream to the heart, digestive organs and other tissues. Only 50% of the cases in the acute phase experience symptoms such as fever, headache, swollen eyelids, enlarged lymph glands, muscle pain or difficulty in breathing. Following the acute phase, most patients enter into a prolonged asymptomatic chronic phase in which the parasites can be found, hidden in the heart and digestive organs. Up to 30% of the patients suffer from cardiac disorders and 10% have digestive, neurological or mixed problems. The rest of the infected persons continue to be asymptomatic. Diagnosis is based on the microscopic examination of parasites in blood via blood smears and with serological confirmation tests. Once the diagnosis is confirmed, the patient receives benznidazole and nifurtimox, and additional symptomatic treatment when cardiac or gastrointestinal problems occur.
Control for Chagas disease is defined as: to interrupt transmission through blood transfusion in the Americas, European and Western Pacific regions by 2015; to interrupt intradomiciliary vectorial transmission in Latin America by 2020; and improved health-care access for the infected population by 2020. Up till now, the risk of transmission by blood transfusion has been substantially reduced throughout Latin America, e.g. 20 of the 21 countries have achieved 100% screening of blood.