Without the White Coat
By Florentino P. Alerta II, M.D.

Malaria… not just a mosquito bite

Disturbing it may be, it has been a bite of an ordinary mosquito that took the life of a TV journalist after contacting malaria in Palawan. It simply shows that there are a lot of plasmodium out there. The ordinary Filipino will always be in the losing end once he contracts the infection of malaria. Thus, a little knowledge of malarial infection will at least help us in taking some actions or steps in dealing with the infection.

It was in the year 1882 when the first “plasmodium” was discovered by microscope and found in red blood cells of patients infected with malarial infection. It was the bad smelling stagnant water that gave malaria its name, in which in this environment mosquitoes carrying this plasmodium thrives. In latin, “MALA” means bad, “ ARIA” meaning air, when put together spells the word “MALARIA” meaning “Bad Air”. Malaria is a parasitic infection, a protozoan (only one cell organism). There are many species that infect animals, but 4 species of interest infects man, Plamosdium malariae(quartan), Plasmodium vivax (benign tertian), Plasmodium falciparum (malignant tertian), and Plasmodium ovale (ovale tertian). Like other parasites the plasmodium undergoes different stages of development in which it changes into different forms. Two hosts are involved in malarial infection the human host and the anopheles mosquito in order to complete its development. In the human stage development which involves the sporozoite, schizont, hynozoite, merozoite, trophozoite and lastly the gametocyte. The stages in the mosquito or anopheles stage composed of the gametocyte, gamete, zygote, ookinete, oocyts, and lastly the sporozoite. A simple understanding of the life cycle of the plasmodia will further give us some insights in its prevention and protection. The life cycle involves 2 phases, the asexual phase that happens in the human intermediate host and the sexual phase in the female anopheles mosquito which serves as the definitive host. (Why the female mosquito? It is the female mosquito that needs the human blood in order to produce her eggs and at the same time transmit the infective stages of plasmodium thus man is infected by the bite of the mosquito.) The human host is infected by the sporozoite from the female anopheles, these sporozoites are carried into the general circulation and will finally invade the liver parenchymal cells and further undergoing development. It is not only through the bite of the mosquito that transmission occurs, but also through blood transfusion and conatal transfusion (when the placenta separates there is a mixing of maternal and fetal blood, thus infected maternal blood with merozoites invade the red blood cells of the fetus.) In some cases and instances infected and contaminated needles can also be seen as a way of transmission among intravenous drug users.

The first clinical sign of malarial infection is fever, so the incubation period is the interval between the infection and the surfacing of the first clinical sign like fever. The primary attack is shown by symptoms of fever with chills, rigor, sweating and prostration. The fever is caused by the release of pyrogenic parasite metabolites during RBC ruptures and release of merozoites. Remember that malarial infection can lay dormant for the longest, 53 years on P. malariae and less than a year for P. falcifarum and P. vivax. All clinical manifestation of a malarial infection are of protein in nature and difficult to differentiate from any febrile, and tropical infection. Don't forget with malarial infection expect involvement of all organ system of the body that utilizes oxygen and is disrupted with the destruction of red blood cells thus causing further anoxia.

For the community it is always our personal hygiene that counts a lot, cleaning our surroundings with the likes of dengue and other mosquito disease ridden infection the eradication of these insects is the main priority. Again empty containers of stagnant water and eliminate suspected breeding areas where mosquito exists and thrive.