The number of cases and deaths related to malaria has been declining steadily for 15 years, but the mosquito-transmitted disease continues to kill more than 400,000 people each year. Ninety per cent of the deaths occur in sub-Saharan Africa. Seventy per cent are children.
According to the World Health Organization, approximately 3.2 billion people (nearly half of the world’s population) were at risk of malaria in 2015 and 95 countries and territories had ongoing malaria transmission. Some groups are at higher risk of contracting malaria, and developing severe disease, than others – including infants, children under five years of age, pregnant women, and people living with HIV/AIDS.
Suffering and loss of life from malaria are tragically unnecessary because the disease is largely preventable, detectable and treatable.
Malaria: Quick Facts
- Transmission: Malaria is a parasitic infection transmitted by the bite of female Anopheles mosquitoes, which are infected by feeding on a person carrying parasites.
- Signs and symptoms: Malaria begins as a flu-like illness, with symptoms including fever, joint pain, headaches, frequent vomiting, convulsions and coma. If left untreated, it can become severe. Death from malaria may be due to brain damage (cerebral malaria), or damage to vital organs.
- Diagnosis: Diagnosing malaria is done with rapid tests or looking for the parasite under a microscope in a blood smear.
- Treatment: Artemisinin-based combination therapy is the most effective treatment. A course of antimalarial pills for a baby can cost as little as 32 cents.
- Prevention and control: Insecticide-treated mosquito nets and indoor residual spraying are the main methods of prevention; malaria can also be prevented by using antimalarial medicines, also known as 'chemoprophylaxis'.
What causes malaria?
Malaria is a parasitic infection transmitted from person to person by the bite of infected female Anopheles mosquitoes. These mosquitoes usually bite from dusk to dawn.
Once transferred to the human body, the infection travels to the liver where it multiplies and then enters the red blood cells. Inside the red blood cells the parasites multiply rapidly until they burst through the cell walls, releasing even more parasites into the blood stream.
There are four main species of the malaria parasite: Plasmodium falciparum, Plasmodium malariae, Plasmodium vivax and Plasmodium ovale. P. falciparum is the main cause of severe malaria and death.
Symptoms of malaria
Malaria begins as a flu-like illness, with symptoms first occurring nine to 14 days after infection. Symptoms include fever (cycles of fever, chills and sweating may develop), joint pain, headaches, vomiting and convulsions. Coma may ensue.
If simple malaria is left untreated, it can become severe — around eight million malaria cases progress to severe malaria annually. Death from malaria may be due to brain damage (cerebral malaria), or damage to vital organs. The reduction of red blood cells can cause anemia.
Diagnosing malaria is done with rapid dipstick tests or by looking for the parasite under a microscope in a blood smear. However, rapid tests are not always available, and microscopy is not always straightforward. As a result, diagnosis based on symptoms is still normal in much of the developing world.
This means patients are often misdiagnosed and the real reasons for their symptoms go untreated. It also means that anti-malarial drugs are overused and go to waste when they are desperately needed.
The most effective treatment for malaria is artemisinin-based combination therapy (ACTs). ACTs have low toxicity, few side effects and act rapidly against the parasite.
Today, 41 out of 54 African countries have protocols that recommend ACTs as a first-line treatment for malaria. But in many places where MSF works, ACTs are scarce. The global need for ACTs is estimated to be at 300 to 500 million treatment courses per year, however, in 2006, drugs for less than 90 million treatments were purchased.
A three-day course of anti-malarial pills for a baby can cost as little as 32 cents.
Long lasting insecticide-treated bed nets are an important means of controlling malaria. In endemic areas, MSF distributes nets to pregnant women and children under the age of five, who are most vulnerable to severe malaria.
MSF's malaria activities
MSF treated nearly 2.3 million cases of malaria in 2015. Since 2001, the WHO has recommended using artemisinin-based combination therapies to treat malaria. The use of these new treatments contributed significantly to the remarkable reduction in the number of malaria-related deaths in the last 15 years. However, resistance to artemisinin has been documented in some regions – enabled, at least in part, by the use of monotherapies (artemisinin alone, not in combination with other drugs), counterfeit and poor-quality drugs, and treatment interruptions once symptoms have abated. It could get worse and become a greater threat to public health, too, because there will not be any replacements for artemisinin treatment available for several years. In Cambodia, where growing artemisinin resistance is a particular threat, MSF is researching how resistant malaria spreads and evaluating which strategies could contribute to the elimination of the disease locally.
In 2012, MSF teams in Mali and Chad staged one of the first large-scale seasonal malaria chemoprevention (SMC) campaigns, providing pre-emptive malaria treatment to children in places where the disease is seasonally endemic through repeated administration of antimalarials. MSF is now implementing this strategy in five countries, and the strategy has been integrated into the national policies of 13 countries in the Sahel region of Africa with highly seasonal transmission. More than 15 million children should be covered in 2016. This strategy is not intended to become a permanent tool to combat the disease, however. The protective effect of SMC is relative and of limited duration, ceasing several weeks after completed. Thus, it is a valuable approach to save lives in some contexts, but we still need more comprehensive, longer-lasting solutions.
After decades of research, ‘RTS,S’ is the first malaria vaccine to have completed clinical development. However, its efficacy is limited, particularly against the severe forms of the disease, and it is complicated to use. It requires four doses, two of which have to be separated by 18 months. Further pilot studies with this vaccine by other actors will start in 2018. MSF continues to call for ongoing research to develop a safe, efficacious, inexpensive vaccine that is easy to use in developing countries. This is a call that needs to be answered by pharmaceutical companies, research bodies, and national and international health bodies alike if we want the keep up the momentum in the fight against malaria.