Malaria

Malaria is a parasitic infection spread by the bite of infected female Anopheles mosquitoes. Once the parasite is inside the human body, it makes its way to the red blood cells, where parasites multiply rapidly until they burst out of the red blood cells and into the bloodstream.

Infants and children under five years old are especially vulnerable to infection and serious consequences of malaria since they haven't yet developed immunity. People displaced by conflict or natural disaster are also at an increased risk of malaria, often due to living conditions that fuel transmission: inadequate shelter in overcrowded camps near standing water and livestock. Displaced people coming from places where malaria is not common to areas where malaria is common are particularly vulnerable because they lack the partial immunity developed by continuous exposure since childhood; when infected, they tend to get very sick. 

Pregnant women with malaria are at increased risk of anemia, severe sickness, and death; there is also a higher chance that the pregnancy will develop complications or end in miscarriage, or cause fetal growth restriction. 

Malaria often begins as a flu-like illness. Fever typically appears 9-14 days after infection (typical cycles of fever, shaking chills, and drenching sweats may develop) and may be accompanied by multiple non-specific symptoms, which makes clinical diagnosis difficult. The disease also causes the destruction of red blood cells, leading to anemia.  

If simple malaria is not treated, it can become severe, increasing the risk of death. That’s why early diagnosis and quick treatment are vital. Severe malaria parasites that attack the brain can cause seizures and coma, and other severe cases can lead to breathing problems, kidney failure, and/or severe anemia. Each year about eight million malaria patients develop life-threatening complications. 

Malaria-carrying mosquitoes usually bite from dusk to dawn. Since mosquitoes breed in water, they are especially plentiful during the rainy season, causing malaria infections to increase.

The most basic prevention measure is to avoid bites. This can be done through indoor spraying of homes with safe, long-lasting insecticides and/or by sleeping under mosquito nets treated with long-lasting insecticide. More recently, antimalarial drugs have been used to prevent infection among the most at-risk populations for limited periods of time. Seasonal malaria chemoprevention (SMC) is now recommended for children during the highest-transmission months in some regions. Preventive drug treatment is also recommended for pregnant women at routine prenatal care visits after the first trimester of pregnancy, for infants during routine vaccination visits, and at the time of discharge for some hospitalized children.

Diagnosing malaria is usually done with rapid diagnostic tests using blood from a finger prick. The tests are easy to perform, and community health workers can be trained to do them. A more accurate test is done by using a microscope to look directly for malaria parasites in a drop of blood. But most primary health facilities don't have microscopes or trained lab technicians, and microscopy is much more labor-intensive, so this diagnostic test is often not feasible.

In some settings, no testing is available at all, so community health workers must diagnose sick children based on symptoms alone. This often leads to the overdiagnosis of malaria while the real cause of patients’ symptoms goes untreated.

The most effective treatment for malaria is a combination of two drugs known as artemisinin-based combination therapy (ACT), which cures most infections in three days. These ACTs consist of a potent antimalarial from the artemisinin family combined with a second “partner” antimalarial drug.

Early treatment is essential since the longer the disease lasts, the more likely it will progress to severe malaria. Severe malaria requires hospitalization so patients can be given intravenous antimalarials along with supportive treatment. Patients often need blood transfusions, which in turn requires a safe, adequately-stocked blood bank—something that’s difficult to achieve in under-resourced areas, especially in sub-Saharan Africa. 

Without treatment, or with significantly delayed treatment, severe malaria kills. Treatment with artemisinins is usually very effective but the malaria parasite has developed resistance to artemisinin in some regions, particularly in Southeast Asia, meaning that ACT may no longer be effective. If the spread of resistance cannot be stopped, it could mean a resurgence of malaria since there aren’t currently any new drugs available.