Malaria is a communicable disease caused by a protist spread by mosquitoes. Explain how malaria is transmitted from one person to another and describe three ways in which the spread of malaria can be limited.

Malaria is transmitted when a female Anopheles mosquito bites an infected person and takes up the Plasmodium parasites in its blood meal. The parasites develop in the mosquito’s gut and migrate to the salivary glands; when the mosquito bites another person it injects the parasites into the bloodstream, thereby infecting the new host.

Three ways to limit the spread of malaria are:
1. Reduce mosquito breeding sites by removing standing water and improving drainage.
2. Use mosquito nets and repellents to prevent bites, especially at night.
3. Take prophylactic anti‑malarial medication before travelling to endemic areas.