Malaria is a communicable disease caused by a protist spread by mosquitoes. Describe how the spread of malaria can be reduced in a population.

Eduqas A-Level Biology — 3.5 Human impact on the environment · Describe · 5 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Malaria is caused by the protist Plasmodium falciparum. It is transmitted through the bite of a female mosquito vector, which carries the pathogen without being infected itself. Malaria causes damage to blood and the liver and can be fatal.

Model answer (5 marks)

1. Reduce standing water around homes to cut mosquito breeding sites.
2. Use mosquito repellents on skin and clothing to prevent bites.
3. Sleep under insecticide‑treated mosquito nets to create a physical barrier.
4. Take prophylactic anti‑malaria medication before travelling to endemic areas.
5. Target the mosquito vector (e.g. spraying insecticides) to interrupt transmission of Plasmodium to humans.

Examiner tips

Use the exact terms: standing water, mosquito repellents, mosquito nets, anti‑malaria drugs, vector. 5 points, one per bullet.
Show clear cause–effect links: reducing breeding sites lowers mosquito numbers, repellents stop bites, nets block contact, drugs prevent infection, targeting vector stops transmission.

Common mistakes

Mixing up the role of the mosquito (thinking it is infected)
Failing to mention the vector aspect
Using vague phrases like ‘prevent disease’ instead of specific interventions

Mark scheme (5 marks)

Minimise areas of standing water to reduce mosquito breeding sites
Use mosquito repellents to prevent mosquito bites
Use mosquito nets (to prevent bites whilst sleeping / to create a physical barrier between the mosquito and the person)
Take anti-malarial drugs before travelling to countries where malaria is common
The mosquito is a vector, meaning it carries the pathogen without being infected itself, so targeting the mosquito interrupts transmission of the pathogen to humans

Key terms in this question

protist · communicable disease