The incubation period differs depending on the pathogen. After 7 to 40 days, the first uncharacteristic symptoms such as fever, headache and body aches and a general feeling of "sickness" appear. These nonspecific complaints are often misinterpreted as a flu infection or gastrointestinal flu. The interval between a tropical stay and the occurrence of malaria can foster a misdiagnosis in our latitudes.
Forms of malaria
How intense the symptoms are depends on the degree of immunity of the infected person. Multiple infected individuals acquire a so-called semi-immunity, which prevents a particularly serious illness. Non-immune are at greatest risk - especially infants and the elderly.
Plasmodium ovale and vivax trigger a malaria tertiana. In this form, after a few days, a regular rhythm of fever attacks sets in, which then occurs every 48 hours. It comes in the late afternoon to chills, the fever rises rapidly to levels around 40 ° C. After three to four hours, the fever, accompanied by strong sweats, returns to normal levels.
Malaria quartana is the rarest form of malaria and is caused by Plasmodium malariae. The fever episodes occur in a rhythm of 72 hours. Both forms usually heal without treatment within 8 weeks.
The Malaria tropica is the most dangerous form of malaria, in non-immune, it ends untreated in 20% of cases fatal. In contrast to the other malaria types, no rhythmic intermittent fever occurs, which makes the diagnosis more difficult. In more than half of those affected, the platelets fall off, which can lead to coagulation disorders, as well as enlargement of the spleen or liver and diarrhea. If infestation of the nervous system seizures and consciousness clouding come to it. Complications include acute renal failure and circulatory collapse.
The prognosis of the malaria tertiana and quartana is good, this also applies to an early treated malaria tropica. Mortality from malaria is only 2% in Germany. However, malaria parasites have the ability to form rest forms that cause relapses after two or five years (Plasmodium vivax and ovale) or even after 40 years (Plasmodium malariae)
Diagnosis of malaria
The most important investigation in malaria suspected is the microscopic examination of the blood. Usually, the so-called "thick drop", an air-dried drop of blood, or sometimes a thin blood smear on pathogens is examined. An experienced doctor can even distinguish the various malaria parasites under the microscope based on their appearance. The number of pathogens in the blood drop reflects the severity of the disease. The detection of pathogens in the blood is the proof of the presence of malaria.
On the other hand, a negative test result does not exclude malaria - possibly the number of parasites in the blood is still too low and the pathogens can only be seen after a test repetition. There are also malaria rapid tests. They can be used by any traveler on site for self-diagnosis. Unfortunately, they sometimes give false test results, as they do not recognize every pathogen and their implementation is not easy.