Chagas disease (American trypanosomiasis; synonyms: Infection by Trypanosoma cruzi; Chagas disease; pseudomyxedema) is an infectious disease caused by flagellates of the genus Trypanosoma (Trypanosoma cruzi).
The following forms of trypanosomiasis can be distinguished:
- African trypanosomiasis (sleeping sickness; ICD-10-GM B56.-) – caused by Trypanosoma brucei gambiense (West African sleeping sickness) and Trypanosoma brucei rhodesiense (East African sleeping sickness).
- American trypanosomiasis (Chagas disease; ICD-10-GM B57.-) – caused by Trypanosoma cruzi.
Chagas disease (American trypanosomiasis) is described below.
The disease belongs to the parasitic zoonoses (animal diseases).
Pathogen reservoirs are many farm and wild animals, but also domestic animals. An infected human also represents a pathogen reservoir.
Occurrence: American trypanosomiasis occurs in Central and South America (and some southern states of the United States).
Transmission of the pathogen (route of infection) occurs primarily through blood-sucking predatory bugs of the genus Triatoma. They are predominantly nocturnal. The predatory bugs excrete the infectious form via feces, and humans become infected by contact or smear infection (fecal-oral: infections in which pathogens excreted with feces (fecal) are ingested via the mouth (oral), e.g., through contaminated drinking water and/or contaminated food). Transmission during organ transplantation or via blood transfusion is also possible.
The pathogen enters parenterally (the pathogen does not penetrate through the intestine), i.e. in this case, it enters the body percutaneously (through the skin) (percutaneous infection).
The incubation period (time from infection to outbreak of the disease) is usually up to 21 days.
The number of people infected worldwide is estimated at around 18 million.
Course and prognosis: The course of the disease depends largely on how early treatment (antibiotics) is started. The earlier, the better. If therapy is started late and changes occur in the heart, the prognosis is unfavorable and complications such as cardiac arrhythmias and pulmonary edema (water retention in the lungs) must be expected. Patients at risk are infants, young children and people with immunodeficiency (immune deficiency).
If left untreated, the lethality rate (mortality in relation to the total number of people suffering from the disease) is up to 10%.
A vaccine against Chagas disease is not yet available.
