Chagas Disease

Chagas disease, also known as American trypanosomiasis, is a tropical parasitic disease caused by the protozoan Trypanosoma cruzi. It is primarily spread to humans and other mammals through the feces of triatomine bugs, often referred to as “kissing bugs,” due to their tendency to bite the faces of humans while they sleep. The disease can also be transmitted through contaminated food or drink, blood transfusions, organ transplants, and from mother to child during pregnancy.

Stages of Chagas Disease

Chagas disease has two main phases: the acute phase and the chronic phase.

• Acute phase: This phase lasts for the first few weeks or months after infection. Many people experience no symptoms or only mild symptoms, which may include fever, fatigue, body aches, headache, rash, loss of appetite, diarrhea, and vomiting. Because the symptoms are non-specific, the acute phase is often overlooked or misdiagnosed.
• Chronic phase: After the acute phase, the disease may enter into a prolonged asymptomatic form, during which few or no parasites are found in the blood. Without treatment, the infection can last a lifetime. Decades after the initial infection, 20-30% of infected individuals will develop severe cardiac and/or gastrointestinal complications, including enlargement of the ventricles of the heart, which can lead to heart failure, and enlargement of the esophagus or colon, leading to difficulties with eating or passing stool.

Diagnosis and Treatment

Diagnosis of Chagas disease is typically made by blood tests, which can detect the presence of T. cruzi parasites or antibodies against them. During the acute phase, the parasites can sometimes be directly observed in the blood under a microscope.

Treatment involves antiparasitic medications, such as benznidazole or nifurtimox, which are most effective during the early stages of infection. In the chronic phase, treatment focuses on managing symptoms and complications of the disease.

Prevention and Control

Prevention efforts are mainly focused on reducing transmission by controlling the population of triatomine bugs, screening blood donations, and testing pregnant women in endemic areas to prevent congenital transmission. Improved housing and living conditions can also reduce the risk of bug infestation and thus the spread of the disease.

Epidemiology

Chagas disease is endemic to 21 countries in Latin America, where it is mostly transmitted to humans by insect vectors. However, due to increased global travel and migration, Chagas disease has been reported in non-endemic countries, including the United States, Canada, many European countries, and some countries in the Western Pacific region. It is estimated that about 6 to 7 million people worldwide are infected with T. cruzi.