# Explain how climate change is predicted to affect the geographic distribution of vector-borne diseases such as malaria.

> IB DP Biology Higher Level (2023 syllabus) — D4.3 Climate change · Explain · 4 marks

> Rising global temperatures and altered precipitation patterns associated with climate change are projected to shift the habitats of disease vectors, with significant implications for human health.

## Mark scheme (4 marks)

1. Rising temperatures allow disease vectors (e.g. Anopheles mosquitoes) to survive and reproduce at higher altitudes and latitudes than previously possible.
2. Warmer temperatures shorten the extrinsic incubation period of the pathogen within the vector, increasing transmission potential.
3. Altered precipitation patterns (increased rainfall or flooding) create more standing water, expanding breeding habitats for vectors.
4. Populations in newly affected regions lack immunity to the disease, making them more vulnerable, so morbidity and mortality are expected to increase in those areas.

## Key terms

- [vector-borne disease](https://www.gradenine.co.uk/glossary/vector-borne-disease)
- [vector](https://www.gradenine.co.uk/glossary/vector)
- [geographic distribution](https://www.gradenine.co.uk/glossary/geographic-distribution)

## Related

- [Revision notes for IB DP Biology Higher Level (2023 syllabus)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-climate-change-is-predicted-b15820dd) · Published by Druglandscape Ltd.