​Infectious Diseases and Microbiology - Malaria ( Plasmodium species)

​Infectious Diseases and Microbiology - Malaria  ( Plasmodium species) 
 Plasmodium species causing malaria.It is a sporozoan parasite that undergoes alternating cycles of sexual and asexual reproduction. The species that cause infections in humans are P vivax, P ovale, P malariae, and P falciparum.
The female Anopheles mosquito serves as both the definitive host and the vector for transmission. The sexual cycle, known as sporogony, takes place within the mosquito host, while the asexual stage, referred to as schizogony, occurs within the human intermediate host. P. vivax and P. ovale have the ability to develop hypnozoites in the liver and remain in a dormant state for an extended period of time.

Malaria is a recurring illness that progresses through three distinct stages. The "cold stage" is characterized by shaking chills, the "hot stage" is characterized by fevers as high as 41°C, and the "sweating stage" is characterized by drenching sweats and weariness.
Additional symptoms include enlargement of the spleen, enlargement of the liver, and a decrease in red blood cells. P. falciparum is responsible for causing severe illness, which includes the blockage of small blood vessels, damage to the brain and kidneys, acute kidney failure, and ultimately, death.

The primary infection attacks hepatocytes. Hepatocyte schizonts liberate many merozoites into the circulatory system.
P. vivax and P. ovale specifically invade reticulocytes, while P. malariae infects mature erythrocytes. P. falciparum, on the other hand, has the ability to infect all types of red blood cells (RBCs). The red blood cells that are infected undergo the formation of a ring-shaped trophozoite, which then develops into a schizont containing 8-24 merozoites. Rupture leads to episodes of fever.

Every species exhibits distinctive microscopic features that are observable in both thick and thin blood smears.
Chloroquine demonstrates efficacy in the erythrocytic phases. Primaquine eradicates dormant liver stages and gametocytes of the malaria parasite P. falciparum for preventive purposes. Nevertheless, the prevalence of chloroquine resistance is high. Other options are Malarone, quinine, quinidine, mefloquine, and pyrimethamine-sulfadoxine. Prevention entails the use of prophylaxis, such as chloroquine or other antimalarial medications, together with bed nets that are treated with pesticide and mosquito repellents.

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