Gamete carriage

Gamete carriage: what is it and how is it related to tropical malaria?

Malaria is one of the most dangerous infectious diseases that kills thousands of people around the world every year. It is caused by protozoan parasites of the genus Plasmodium, which are transmitted to humans through the bites of Anopheles mosquitoes.

One of the forms of the infectious process in tropical malaria is gamete carriage. It is characterized by the presence of Plasmodium falciparum gametocytes in human blood in the absence of clinical signs of the disease. Gametocytes are the form of this parasite that is capable of sexual reproduction in the gastrointestinal tract of Anopheles mosquitoes.

Gamete carriage can be observed in convalescents after malaria, as well as during parasitic “cold” relapses, when parasites are dormant inside the human body and can resume their activity at any time.

Gamete carriage is an important point in the development cycle of the parasite and its transmission from humans to mosquitoes. When a mosquito drinks the blood of a human who is a gamete carrier, the gametocytes enter the mosquito's gastrointestinal tract, where sexual reproduction of the parasite occurs. After this, new infectious forms of the parasite are transmitted by the mosquito to another person, and the malaria development cycle repeats.

Thus, gamete carriage is an important link in the transmission of malaria from person to person through Anopheles mosquitoes. Therefore, when fighting this dangerous disease, it is necessary not only to destroy mosquitoes and treat patients, but also to pay attention to convalescents and those who have suffered malaria in the past in order to prevent gamete carriage and stop the development cycle of the parasite.

**Gameton carriage** is a little-known phenomenon in medicine, which occurs mainly in tropical, less often in tertian (three-day) malaria. It is also characteristic of Plasmodiu falciparum infection. Thus, gametocycled (i.e., living outside the erythrocyte) malarial plasmodium exists simultaneously with normal tissue forms of the pathogen and, in the absence of indications for treatment, it should be classified among them. Indeed, in general, the presence of gametosites in the patient’s blood does not indicate a disease. At the same time, a number of patients may experience a combination of various forms of the pathogen associated with moderate and severe manifestations of the disease, as well as anemia. Thanks to the described phenomenon, a method for diagnosing parasitemia (detection of an infectiously intact parasite in the bitemporal region of both hemispheres of the gombra with red blood cells) has been successfully introduced in a patient by analyzing smears from peripheral blood and/or plasma [1], [2], [3], [4] , [5