Malaria: Causes, Symptoms, Treatment, and Prevention

Malaria is one of the world’s most widespread and dangerous infectious diseases. It is caused by Plasmodium parasites and spreads through the bite of infected female Anopheles mosquitoes. While it is rare in the United States and Europe, malaria remains a major global health challenge, with hundreds of millions of cases and more than 600,000 deaths each year, particularly in sub-Saharan Africa, South Asia, and parts of South America.

Understanding the causes, symptoms, treatments, and prevention methods is essential for both travellers and people living in regions where malaria is common.

What Is Malaria?

Malaria is a life-threatening parasitic infection that targets red blood cells. After entering the body through a mosquito bite, the parasites travel to the liver, multiply, and then re-enter the bloodstream. This cycle leads to fever, chills, and other flu-like symptoms that can escalate to severe complications if untreated.

According to the World Health Organization (WHO), more than 3 billion people live in areas at risk of malaria transmission. Despite global efforts, malaria continues to be one of the leading causes of illness and death in tropical and subtropical regions.

Malaria Causes

Malaria is caused by parasites belonging to the genus Plasmodium. Several species infect humans, and each has different risks and outcomes:

• Plasmodium falciparum: The most dangerous type, responsible for most malaria-related deaths. It multiplies quickly and can cause cerebral malaria. Common in Africa.
• Plasmodium vivax: Can stay dormant in the liver and cause relapses months or years later. Common in Asia and Latin America.
• Plasmodium ovale: Similar to P. vivax, but less widespread. Mainly found in West Africa and Pacific islands.
• Plasmodium malariae: Can cause long-lasting infections, sometimes persisting for life if untreated.
• Plasmodium knowlesi: A parasite usually found in monkeys, but now increasingly recognized as a cause of malaria in humans in Southeast Asia.

Malaria is most commonly spread by mosquito bites but can also be transmitted through:

• Blood transfusion or organ transplant from an infected person
• Sharing contaminated needles or syringes
• Transmission from a pregnant mother to her baby

Malaria Symptoms

Symptoms usually appear 10–15 days after infection, but with certain species, signs may be delayed for weeks or months. Early symptoms can be confused with the flu, which makes diagnosis difficult.

Common malaria symptoms include:

• High fever and chills
• Sweating
• Headache and body pain
• Fatigue and weakness
• Nausea, vomiting, or diarrhea

Severe malaria symptoms include:

• Seizures and confusion
• Breathing difficulties
• Dark or bloody urine
• Jaundice (yellow skin or eyes)
• Kidney or liver failure
• Severe anemia

Without treatment, malaria can lead to coma, brain damage, or death.

Malaria Diagnosis

Doctors diagnose malaria based on symptoms, travel history, and laboratory tests. Key tests include:

• Blood smear microscopy – The gold standard, used to detect the parasite and determine the species.
• Rapid diagnostic tests (RDTs) – Similar to a COVID-19 rapid test, these detect malaria antigens in a drop of blood.
• PCR tests – Identify parasite DNA for more precise diagnosis.
• Antibody tests – Show whether a person has had malaria in the past.

Because parasite levels in the blood can fluctuate, repeated testing may be necessary.

Malaria Treatment

Treatment depends on the species of parasite, severity of infection, and the region where the infection was acquired (due to drug resistance in some areas).

Common Medications:

• Artemisinin-based combination therapy (ACTs) – First-line treatment for P. falciparum.
• Chloroquine – Effective for infections in areas where resistance is not present.
• Primaquine – Prevents relapses of P. vivax and P. ovale.
• Quinine, doxycycline, or clindamycin – Used when ACTs are not available or suitable.
• Intravenous artesunate – Given in severe malaria cases.

Treatment must be started quickly to avoid complications. Pregnant women and children are particularly vulnerable and require careful management.

Malaria Complications

If untreated, malaria can cause life-threatening complications, including:

• Cerebral malaria (brain swelling leading to seizures and coma)
• Organ failure (kidney, liver, or spleen damage)
• Severe anemia due to loss of red blood cells
• Respiratory distress and pulmonary edema
• Very low blood sugar, which may lead to shock

Even after recovery, people may experience long-term fatigue or relapse with certain parasite species.

Malaria Prevention

Preventing malaria is more effective than treating it. The following strategies are recommended:

1. Prevent Mosquito Bites

• Wear long-sleeved clothing and pants.
• Apply EPA-approved repellents such as DEET, picaridin, or oil of lemon eucalyptus.
• Sleep under insecticide-treated bed nets.
• Stay in places with window screens or air conditioning.

2. Take Preventive Medicine (Chemoprophylaxis)

Travelers to high-risk areas may need preventive medication, such as:

• Atovaquone-proguanil (Malarone)
• Doxycycline
• Mefloquine
• Primaquine

Your doctor will prescribe the most suitable option based on your travel destination.

3. Malaria Vaccines

The RTS,S/AS01 (Mosquirix) and R21/Matrix-M vaccines are now recommended for children in high-risk African regions. These vaccines have shown significant success in reducing malaria deaths among young children.

Who Is Most at Risk of Malaria?

• Children under 5 years old
• Pregnant women
• Travelers from non-endemic areas
• People with weakened immune systems (HIV/AIDS patients)

Key Takeaways

Malaria is a preventable and treatable disease but remains a serious health risk in many parts of the world. With proper preventive measures, early diagnosis, and effective treatment, the global burden of malaria can be reduced. If you are traveling to or living in a malaria-endemic area, consult your doctor about preventive medicine and take steps to protect yourself from mosquito bites.