Malaria is one of the most common infectious diseases in the world. It is primarily a tropical illness (especially widespread in Africa) but it can occur practically anywhere due to modern tourism.
Malaria is caused by protozoa known as plasmodium (Plasmodium malariae). Most importantly, the plasmodia live in saliva of female mosquitoes (Anopheles mosquitoes. When a mosquito stings humans, Plasmodium microorganisms can get into the body and via the bloodstream into the liver tissue where they multiply. Plasmodium is periodically released out of the liver into the blood where it attacks red blood cells and causes their break down, which leads to the symptoms. The mosquito bite is also responsible for the so-called airport malaria. It is causes by a mosquito, which gets inside a plane into another country. The airport malaria can occur in airport staff or people living in the close vicinity of the airport.
The basic manifestation is the malaria attack caused by periodic disintegration of red blood cells. It is usually accompanied with a high fever (above 38°C), chills and muscle tremor. According to the frequency of seizures, we distinguish multiple types of malaria. The seizures usually recur every two or three days. In the most severe form of the disease, which is called tropical malaria, the seizures recur several times a day and this form may be often fatal. In a prolonged untreated form of the disease, the patient may suffer from anemic syndrome due to anemia caused by uncompensable excessive destruction of red blood cells. The spleen may get enlarged, which is also related to the destruction of red blood cells.
Malaria is probable in a person with the above-mentioned symptoms, who returned from abroad from countries with occurrence of malaria. Plasmodium can be detected in a blood sample under microscope or serologically by confirming serum antibodies against plasmodium.
Proper prevention is important when planning to travel to a country where there is known occurrence of malaria. The prevention consists of temporary use of antimalarial drugs. However, even a sufficient dose of these drugs does not mean a total protection and therefore it is advisable to protect in other ways – exclude contact with mosquitoes by using repellents and mosquito nets. A suitable method of prevention can be discussed with doctors specialized in issue of tropical medicine.
There is also a natural protection against malaria, which is known as sickle-cell anemia. It is a genetic mutation, which is widespread among African population, and which increases the resistance of red blood cells against plasmodium microorganism. This effect is clearly positive, but on the other hand the mutation causes changes of red blood cells’ shape resulting in their increased disintegration. In people who do not live in areas with malaria occurrence, the mutation is rather harmful. Read more in related article.
The therapy includes regular administration of antimalarial drugs, which kill plasmodium microorganisms. The original substance is quinine, which is a bitter product of Cinchona tree.