Trypanosoma cruzi is a single-celled parasite that causes Chagas disease, primarily found in parts of Central and South America. It is transmitted to humans through the bite of infected triatomine bugs, also known as kissing bugs. The parasite can also be spread through blood transfusions, organ transplants, and from mother to child during pregnancy. Once inside the human body, Trypanosoma cruzi can invade various tissues, particularly the heart and digestive system. Symptoms of Chagas disease can range from mild to severe, including fever, fatigue, and swelling. If left untreated, it can lead to serious health complications over time.