Back to: MICROBIOLOGY 300 LEVEL
Welcome to class!
Hello, superstar! It’s so good to have you here again. You’ve been doing a fantastic job learning about parasites and how they affect the human body. Today’s topic is very close to home for many Nigerians and Africans in general—Plasmodium spp. (Malaria). Whether you’ve experienced malaria yourself, seen a family member fall ill, or heard of it on the news, this lesson will help you understand what causes it, how it spreads, and how it can be controlled.
Plasmodium Spp. (Malaria)
Malaria is one of the most common and serious diseases in tropical countries like Nigeria. It is caused by a microscopic parasite from the Plasmodium genus. This parasite is transmitted through the bite of an infected female Anopheles mosquito—especially the ones that bite at night.
When the mosquito bites, it’s like she’s giving you more than just an itchy spot—she’s injecting you with tiny invaders that can make you very sick. Understanding Plasmodium helps us protect ourselves, treat malaria properly, and even save lives.
Types of Plasmodium Species
There are several species of Plasmodium, but only five cause malaria in humans:
Plasmodium falciparum – Most dangerous and common in Nigeria; can lead to severe complications and death.
Plasmodium vivax – Causes milder illness but can relapse after months.
Plasmodium ovale – Similar to vivax, found in West Africa.
Plasmodium malariae – Causes long-lasting infection with fewer symptoms.
Plasmodium knowlesi – Found in Southeast Asia; rare in Africa.
Life Cycle of Plasmodium
Plasmodium has an indirect life cycle, involving two hosts:
Human host – where the parasite multiplies in the liver and red blood cells.
Mosquito vector – where sexual reproduction occurs.
Here’s how it works:
A mosquito bites an infected person and picks up Plasmodium from their blood.
The parasite develops in the mosquito and becomes infectious.
When the mosquito bites someone else, it injects the parasite into their blood.
Malaria is transmitted to people and animals by mosquitoes. Malarial sporozoites develop inside oocysts and are released in large numbers into the hemocoel of Anopheles stephensi mosquitoes. This false-colored electron micrograph shows a sporozoite migrating through the cytoplasm of midgut epithelia. See Frevert et al.
Image Credit: Image by Ute Frevert; false color by Margaret Shear
In the human body, the parasite travels to the liver, multiplies, then invades red blood cells.
This cycle causes the symptoms of malaria—fever, chills, sweating, headache, and body pain.
Symptoms of Malaria
High fever (often every 2–3 days in cycles)
Chills and sweating
Headache
Vomiting or nausea
Muscle and joint pain
Anaemia (due to destruction of red blood cells)
In severe cases: coma, seizures, or death (especially with P. falciparum)
Diagnosis and Treatment
Diagnosis is usually done by looking at a blood smear under a microscope or using rapid diagnostic tests (RDTs).
Treatment includes antimalarial drugs like:
Artemisinin-based combination therapies (ACTs) – most effective.
Others include quinine, chloroquine (though many parasites are now resistant), and mefloquine.
Prevention and Control
Use insecticide-treated bed nets (ITNs).
Indoor residual spraying to kill mosquitoes.
Eliminate stagnant water to reduce mosquito breeding.
Take preventive medication when travelling to malaria-endemic areas.
Prompt treatment of infected individuals to stop the cycle.
Think of Plasmodium like a thief who breaks into your house (body) at night with the help of a friend (the mosquito). Once inside, he hides in the kitchen (your liver), makes copies of himself, and then spreads to every room (your blood). That’s when the chaos begins—breaking your “furniture” (red blood cells) and making you feel very ill. But with the right “security system” (bed nets, clean environment, and medication), you can keep the thief out!
Summary
- Malaria is caused by Plasmodium species, especially P. falciparum.
- It is spread by female Anopheles mosquitoes.
- Symptoms include fever, chills, and anaemia.
- It’s diagnosed through blood tests and treated with antimalarial drugs.
- Prevention includes bed nets, mosquito control, and early treatment.
Evaluation
- What parasite causes malaria, and how is it transmitted?
- Which species of Plasmodium is most deadly?
- What are three common symptoms of malaria?
- Mention two methods used to prevent malaria.
- Why is prompt treatment of malaria important?
You’ve just gained one of the most important pieces of knowledge for any health-minded African—you now understand malaria from the inside out! That’s powerful. With this knowledge, you can protect yourself and educate others. Keep being curious and committed, because Afrilearn is here to make learning exciting, personal, and impactful. Keep shining, and see you in the next lesson, champion!