Life cycle of malaria

Answer 1

The life cycle of malaria involves the transmission of the disease between humans and mosquitoes. It consists of several stages, including the liver stage, blood stage, and mosquito stage. Here is an overview of the different phases in the life cycle of malaria:

1. Transmission: The life cycle begins when a female Anopheles mosquito carrying the Plasmodium parasite bites an infected human. During the blood meal, the mosquito ingests the malaria parasites present in the bloodstream of the infected individual.

2. Sporozoite Stage: Once inside the mosquito's body, the malaria parasites enter the salivary glands and develop into sporozoites. These sporozoites are the infective form of the parasite and are ready to be transmitted to another human host.

3. Injection: When the infected mosquito bites another human, it injects the sporozoites into the bloodstream. From here, the sporozoites rapidly enter the liver cells.

4. Liver Stage (Exoerythrocytic Stage): Inside the liver cells, the sporozoites develop into merozoites, which remain dormant until they are released into the bloodstream. This stage typically lasts around 6 to 15 days, depending on the Plasmodium species.

5. Blood Stage (Erythrocytic Stage): The merozoites released into the bloodstream invade red blood cells (erythrocytes). Within the erythrocytes, the merozoites multiply asexually by undergoing multiple rounds of replication. This results in the destruction of the infected red blood cells, causing fever and other symptoms of malaria.

6. Clinical Stage: The symptoms and severity of malaria vary depending on the Plasmodium species. Common symptoms include fever, chills, headaches, muscle aches, and fatigue. Without proper treatment, malaria can progress and potentially lead to severe complications or death.

7. Gametocyte Stage: Within the bloodstream, a small proportion of the malaria parasites differentiate into sexual forms called gametocytes. These gametocytes are required for the transmission of the disease back to mosquitoes.

8. Mosquito Stage (Exogenous Sporogonic Cycle): When a mosquito bites an infected human with gametocytes in their bloodstream, it ingests the gametocytes. Inside the mosquito, the gametocytes develop into male and female gametes, which fuse together to form a zygote.

9. Ookinete and Oocyst Formation: The zygote develops into a motile form called an ookinete, which penetrates the midgut wall of the mosquito. It then transforms into an oocyst, where multiple rounds of division occur, generating thousands of sporozoites.

10. Release of Sporozoites: The oocysts rupture and release sporozoites into the mosquito's body cavity. These sporozoites then migrate to the mosquito's salivary glands, ready to infect another human host.

The life cycle of malaria is completed when the infected mosquito bites a new human, transmitting the sporozoites and initiating another round of infection. Proper control measures, such as mosquito control and early diagnosis and treatment, are crucial in preventing the spread of malaria.