Diagnosis
If there is a suspicion of Chagas’ disease based on the signs a patient shows, various tests can be performed. In the acute stage of Chagas’ disease, it is sometimes possible to detect the pathogen directly microscopically in blood smears or samples of body tissue. In the chronic phase of Chagas’ disease, the main aim is to detect antibodies against trypanosomes.
Antibodies are special proteins that are produced by the immune cells (immune system) of the body to fight pathogens. Another way of detecting the pathogen is the so-called “xenodiagnosis”. This is a procedure that is used mainly in the countries where Chagas disease is spread.
Here, predatory bugs bred in the laboratory, which have not yet come into contact with trypanosomes, are fixed to the patient’s skin so that they take a blood meal. After a few weeks, trypanosomes are then searched for in the digestive tract of these bugs. If they are found, then it is known that the patient in question actually suffers from Chagas disease.
Therapy
In principle, the earlier Chagas disease is detected, the better it can be treated. The two substances recommended by the WHO, nifurtimox and benznidazole, are available for drug therapy. Unfortunately, both drugs have a wide range of side effects and their effectiveness is also controversial. The use of drugs can cause psychological changes, drowsiness and gastrointestinal disorders such as diarrhoea and vomiting, accompanied by weight loss. Nifurtimox and benznidazole are not approved in Germany, Austria and Switzerland.
Prophylaxis
Since no vaccines against Chagas’ disease are currently available, the focus is mainly on the control of predatory bugs as carriers of the pathogens. As the pirate bugs like to spend the day in small wooden cracks, wattle and straw, it would be very effective to build brick or concrete buildings with a solid roof, but of course this is not possible in many areas, so insecticides are mainly sprayed. Floor-length mosquito nets also offer good protection.
