prevalence and risk factors of malaria

Malaria: Prevalence and Risk Factors

🦟 Malaria is a life‑threatening disease caused by the parasite Plasmodium, transmitted by the bite of infected female Anopheles mosquitoes. It remains a major public health issue, especially in tropical and subtropical regions.

Prevalence Around the World

📈 The numbers show that Sub‑Saharan Africa carries the highest burden, with 70 % of global cases. The disease is less common in temperate zones because the mosquito’s life cycle cannot survive cold temperatures.

Key Risk Factors

• 🌱 Climate – Warm, humid environments with standing water are ideal for mosquito breeding.
• 🏠 Housing – Poorly screened windows and open eaves allow mosquitoes easy access.
• 💰 Socio‑economic status – Limited access to healthcare and preventive measures increases vulnerability.
• 🧪 Drug resistance – Parasite strains that survive antimalarial drugs raise the risk of treatment failure.
• 🦟 Vector density – High numbers of Anopheles mosquitoes amplify transmission.

Think of the mosquito as a tiny delivery truck that carries the parasite from one person to another. If the truck fleet is large (high vector density) and the roads (environment) are wet and warm, the delivery rate skyrockets.

Transmission Cycle (Simplified)

1. 🦟 A female mosquito bites an infected person and ingests the parasite.
2. 🔬 Inside the mosquito, the parasite multiplies and migrates to the salivary glands.
3. 🦟 The mosquito bites another person, injecting the parasite into the bloodstream.
4. 🧬 The parasite infects red blood cells, causing fever, chills, and other symptoms.

The cycle repeats, creating a self‑sustaining loop until the parasite is cleared or the mosquito dies.

Prevention & Control Measures

• 🛡️ Insecticide‑treated bed nets (ITNs) – Block mosquito bites during sleep.
• 🌿 Indoor residual spraying (IRS) – Apply insecticide to walls to kill resting mosquitoes.
• 💊 Prophylactic antimalarials – Taken by travellers to high‑risk areas.
• 🚰 Environmental management – Drain stagnant water and improve drainage.

The combination of these measures is like building a fortress: each layer makes it harder for the parasite to reach people.

Exam Tips for A‑Level Geography

📚 Remember the key terms: vector, parasite, endemic, epidemic, R₀. 📚 Use the cause–effect structure: Identify risk factor → explain how it increases prevalence. 📚 Include data: Cite figures from the prevalence table to support your argument. 📚 Illustrate with an analogy: Helps demonstrate understanding and makes your answer memorable. 📚 Answer in concise, clear sentences: Aim for 2–3 sentences per point.

Good luck! Remember, a clear structure and real‑world examples will set your answer apart. 🚀