Overview

Malaria is a potentially life-threatening disease caused by a parasite and transmitted to humans through the bites of infected mosquitoes—mainly certain types of female Anopheles mosquitoes. Although most common in tropical regions, malaria is both preventable and curable.

The disease is not spread directly from person to person. Instead, infection occurs when a mosquito carrying malaria parasites bites a person, transferring the parasite into the bloodstream. It can also be transmitted through blood transfusions and contaminated needles.

Malaria symptoms range from mild to severe. Common symptoms include fever, chills, and headache, while more serious cases can involve extreme fatigue, confusion, seizures, difficulty breathing, and other complications. If untreated, malaria caused by Plasmodium falciparum can lead to severe illness and death within 24 hours.

Certain groups are at higher risk of severe malaria:

  • Infants and young children

  • Pregnant women

  • People with HIV or AIDS

  • Travelers to malaria-endemic areas

Causes and Parasite Types

Malaria is caused by Plasmodium parasites. There are five known species that infect humans:

  • P. falciparum – the deadliest and most prevalent in sub-Saharan Africa

  • P. vivax – dominant in many regions outside Africa

  • P. malariae

  • P. ovale

  • P. knowlesi

Symptoms

Malaria symptoms typically develop 10–15 days after being bitten by an infected mosquito. Early signs include:

  • Fever

  • Headache

  • Chills

Symptoms can be mild, especially in individuals who’ve had malaria before. However, early testing is critical because many malaria symptoms resemble other febrile illnesses.

Severe malaria symptoms may include:

  • Intense fatigue

  • Confusion or impaired consciousness

  • Seizures

  • Trouble breathing

  • Dark or bloody urine

  • Jaundice (yellowing of skin and eyes)

  • Abnormal bleeding

Pregnant individuals with malaria risk premature delivery or delivering babies with low birth weight. Emergency care is required for anyone showing signs of severe infection.

Global Disease Burden

According to the latest estimates, 263 million cases of malaria were recorded globally in 2023, an increase from 252 million in 2022. Malaria caused approximately 597,000 deaths in 2023.

The WHO African Region accounts for 94% of global cases and 95% of deaths. Children under five represent 76% of all malaria-related deaths in the region, with the majority occurring in four countries:

  • Nigeria

  • Democratic Republic of the Congo

  • Niger

  • United Republic of Tanzania

Prevention

Malaria is preventable through a combination of mosquito bite avoidance and prophylactic medications. Travelers should consult a healthcare provider for preventive medicine before visiting malaria-endemic areas.

Ways to reduce the risk of mosquito bites include:

  • Sleeping under insecticide-treated mosquito nets

  • Applying mosquito repellents (DEET, IR3535, or Icaridin) after dusk

  • Using mosquito coils or vaporizers indoors

  • Wearing protective clothing

  • Installing screens on windows and doors

Vector Control

Vector control is a cornerstone of malaria prevention. The two main methods are:

  • Insecticide-treated nets (ITNs)

  • Indoor residual spraying (IRS)

However, rising insecticide resistance among mosquitoes—particularly Anopheles stephensi, which thrives in urban settings—is a growing challenge. New-generation nets offer broader protection and are becoming more widely used in malaria-endemic regions.

Chemoprophylaxis for Travelers

Travelers heading to areas with high malaria risk should begin chemoprophylaxis weeks before travel and continue the regimen during and after their stay. These medications prevent parasites from maturing in the liver and bloodstream, reducing the risk of illness.

Preventive Chemotherapy

Preventive chemotherapy is the use of antimalarial medications to protect at-risk populations during peak transmission seasons. This strategy includes:

  • Seasonal malaria chemoprevention (SMC)

  • Perennial malaria chemoprevention (PMC)

  • Intermittent preventive treatment for pregnancy (IPTp)

  • Intermittent preventive treatment for school-aged children (IPTsc)

  • Post-discharge malaria chemoprevention (PDMC)

  • Mass drug administration (MDA)

These approaches complement vector control, early diagnosis, and prompt treatment.

Vaccines

Since 2021, WHO has recommended the RTS,S/AS01 vaccine for children in areas with moderate to high P. falciparum transmission. It significantly reduces the risk of both general and severe malaria.

In 2023, WHO also endorsed a second vaccine, R21/Matrix-M, which offers a similar level of protection. Both vaccines are now being introduced into routine childhood immunization programs across Africa and are expected to save thousands of lives when combined with other interventions.

Living With Malaria

Malaria is a serious, but treatable condition that is caused by parasites and transmitted through mosquito bites. The disease remains one of the most common public health problems worldwide. While malaria is less common in the U.S., you may contract the condition if you travel to tropical environments where the disease is more common.

If you develop symptoms of malaria or feel sick after you return from your travels, it's good practice to see your healthcare provider for care. They can learn more about your symptoms, order tests that offer a proper diagnosis, and get you started on treatments. If malaria is left untreated, you may be at risk of developing life-threatening complications. That's why receiving the proper care as soon as possible is important.