Synonyms in a broader sense
Chagas disease, American/South American trypanosomiasis
Definition
Chagas disease is an infectious disease caused by a specific parasite called “Trypanosoma cruzi”. Chagas disease was first described in 1909 by the Brazilian physician Carlos Chagas and is named after him.
Distribution
Since the pathogen Trypanosoma cruzi (Chagas disease) has its natural habitat in Central and South America, the disease is also mainly spread there. However, cases of the disease are increasingly being introduced into other countries such as Spain and the USA, where many immigrants from Latin America live. In total, it is estimated that there are about 16-18 million infected people worldwide.
Pathogen
The pathogen Trypanosoma cruzi is a typical parasite, i.e. a living being that is dependent on another organism and causes damage to it. Among parasites, the pathogen causing Chagas’ disease is counted among the unicellular organisms, or more precisely among the flagellates, and is found mainly in dogs, cats, rodents and armadillos. From these animals Trypanosoma is transmitted to humans via a nocturnal predatory bug.
These predatory bugs usually live in slum areas in close proximity to humans and seek shelter in small cracks or thatched roofs during the day. At night, the bugs use thermoreceptors to visit humans and, immediately after their blood meal, they deposit a droppings drop that may contain trypanosomes. When the bug bites the skin, the person affected feels an itch and, under certain circumstances, rubs the Chagas disease pathogen directly into the resulting wound, thus starting the actual infection. In addition to the transmission of trypanosomes by predatory bugs, infections are also possible through blood transfusions, organ transplantation or breast milk.
Symptoms
If a person is infected with trypanosomes, this does not necessarily mean that he or she will also become ill (Chagas disease). In 60-70% of cases, infections with trypanosomes occur without any signs of disease. If symptoms do occur, these are usually lesions at the site of the bug’s injection, especially redness and swelling.
These lesions are also known as “chagoma”. If such a chagoma is located on the eyelid, it is also called the “Romana sign”. This is very characteristic for an infection with trypanosomes, as the eyelids can easily be attacked by the nocturnal bugs.
Finally, the head of a sleeping person is usually not covered by a blanket and the skin on the eye is particularly thin. About two weeks after transmission by the bugs, the trypanosomes are transferred into the human blood system. This activates the body’s own immune defence and brings about a general feeling of illness and malaise, fever, swelling of the lymph nodes, possibly reddening of the skin and enlargement of the liver and spleen.
An inflammation of the heart muscle is feared as a complication of the disease at this stage. Most patients recover from this acute phase within 1 to 2 months and then subjectively feel healthy again, lymph node swelling and enlargement of the liver and spleen are no longer present. This phase without symptoms can last 10-20 years and is also called the latent phase.
However, while the patient actually feels well, the trypanosomes survive and multiply in the human body, especially in muscle cells and connective tissue cells. In about 60% of cases, this eventually leads to “Chagas syndrome”, which is the chronic phase of the disease. Chagas syndrome is characterized by diseases of the heart (heart failure, low blood pressure, very slow pulse), enlargement of the internal organs, difficulty swallowing due to inflammation of the esophagus, flatulence, constipation and involvement of the central nervous system (brain and spinal cord), the prognosis is often poor.
