WHICH OF THE FOLLOWING IS AN EXAMPLE OF A MICROORGANISM IN ACTION AS A DISEASE VECTOR

• A. Fungi decomposing dead plant material
• B. Mosquito transmitting malaria ✓
• C. Bacteria causing food poisoning
• D. Algae producing oxygen through photosynthesis

The answer to the question is: B. Mosquito transmitting malaria

Mosquitoes are well-known disease vectors, capable of transmitting various diseases to humans and animals. One prominent example is the transmission of malaria, a life-threatening disease caused by the parasite Plasmodium. Female Anopheles mosquitoes are responsible for transmitting this disease.

When a mosquito feeds on an infected human or animal, it ingests the Plasmodium parasites along with the blood meal. Within the mosquito’s gut, the parasites undergo a complex developmental cycle, eventually forming sporozoites. These sporozoites migrate to the mosquito’s salivary glands, where they can be injected into a new host during subsequent blood-feeding.

Once inside a human host, the injected sporozoites travel to the liver and infect hepatocytes, initiating the liver stage of the disease. After a period of multiplication and differentiation, thousands of merozoites are released from each infected hepatocyte. These merozoites invade red blood cells, leading to the symptomatic blood stage of malaria.

The infected individual may experience recurrent episodes of fever, chills, and flu-like symptoms due to cycles of red blood cell destruction and parasite replication. In some cases, severe complications can arise, such as cerebral malaria or organ failure.

Controlling mosquito populations and implementing preventive measures like bed nets, insect repellents, and antimalarial drugs have been effective strategies in reducing malaria transmission.