Malaria is a mosquito-borne infectious disease that affects humans and other animals. Because the parasites that cause malaria affect red blood cells, people can also catch malaria from exposure to infected blood, including:
- From mother to unborn child
- Through blood transfusions
- By sharing needles used to inject drugs
Symptoms of malaria
Signs and symptoms of malaria may include:
- General feeling of discomfort
- Nausea and vomiting
- Abdominal pain
- Muscle or joint pain
- Rapid breathing
- Rapid heart rate
Some people who have malaria experience cycles of malaria “attacks.” An attack usually starts with shivering and chills, followed by a high fever, followed by sweating and a return to normal temperature.
Malaria signs and symptoms typically begin within a few weeks after being bitten by an infected mosquito. However, some types of malaria parasites can lie dormant in your body for up to a year
Causes of malaria
Malaria is caused by a single-celled parasite of the genus plasmodium. The parasite is transmitted to humans most commonly through the bites of infected female Anopheles mosquitoes
Types of malaria
Five species of Plasmodium (single-celled parasites) can infect humans and cause illness:
- Plasmodium falciparum (or P. falciparum)
- Plasmodium malariae (or P. malariae)
- Plasmodium vivax (or P. vivax)
- Plasmodium ovale (or P. ovale)
- Plasmodium knowlesi (or P. knowlesi)
Falciparum malaria is potentially life threatening. Patients with severe falciparum malaria may develop liver and kidney failure, convulsions, and coma. Although occasionally severe, infections with P. vivax and P. ovale generally cause less serious illness, but the parasites can remain dormant in the liver for many months, causing a reappearance of symptoms months or even years later.
Treatment of malaria
Malaria is treated with antimalarial medications; the ones used depend on the type and severity of the disease. While medications against medications against fever are commonly used, their effects on outcomes are not clear. Providing free antimalarial drugs to households may reduce childhood deaths when used appropriately. Programs that presumptively treat all causes of fever with antimalarial drugs may lead to overuse of antimalarial and undertreat other causes of fever. Nevertheless, the use of malaria rapid-diagnostic kits can help to reduce over-usage of antimalarial.
Prevention of malaria
- Awareness of risk – find out whether you’re at risk of getting malaria.
- Bite prevention – avoid mosquito bites by using insect repellent, covering your arms and legs, and using a mosquito net.
- Check whether you need to take malaria prevention tablets – if you do, make sure you take the right antimalarial tablets at the right dose, and finish the course.
- Diagnosis – seek immediate medical advice if you have malaria symptoms including up to a year after you return from travelling.
These are outlined in more detail below.
Being aware of the risks
To check whether you need to take preventative malaria treatment for the countries you’re visiting, see the fit for Travel website.
It’s also important to visit your GP or local travel clinic for malaria advice as soon as you know where you’re going to be travelling.
Even if you grew up in a country where malaria is common, you still need to take precautions to protect yourself from infection if you’re travelling to a risk area.
Nobody has complete immunity to malaria, and any level of natural protection you may have had is quickly lost when you move out of a risk area.
It’s not possible to avoid mosquito bites completely, but the less you’re bitten, the less likely you are to get malaria.
To avoid being bitten:
- Stay somewhere that has effective air conditioning and screening on doors and windows. If this isn’t possible, make sure doors and windows close properly.
- If you’re not sleeping in an air-conditioned room, sleep under an intact mosquito net that’s been treated with insecticide.
- Use insect repellent on your skin and in sleeping environments. Remember to reapply it frequently. The most effective repellents contain diethyltoluamide (DEET) and are available in sprays, roll-ons, sticks and creams.
- Wear light, loose-fitting trousers rather than shorts, and wear shirts with long sleeves. This is particularly important during early evening and at night, when mosquitoes prefer to feed.
There’s no evidence to suggest homeopathic remedies, electronic buzzers, vitamins B1 or B12, garlic, yeast extract spread (such as Marmite), tea tree oils or bath oils offer any protection against mosquito bites.
- Antimalarial tablets
- Preventive medicine
Risk factors for malaria
Human behavior, often dictated by socioeconomic situations, can influence the risk of malaria for individuals and communities. For example:
- Poverty-stricken rural populations in malaria-endemic areas frequently cannot afford the housing and bed nets, which would protect them from exposure to mosquitoes. These individuals often are uninformed about the common manifestations of malaria and the importance of prompt and proper treatment. Often, cultural beliefs result in use of traditional, but ineffective, methods of treatment.
- Travelers from non-endemic areas may disregard the use of insect repellent or prophylactic malarial medicines, due to cost, inconvenience, or a lack of knowledge.
- Standing water in irrigation ditches or burrow pits can be breeding sites for larvae.
- Agricultural work, such as harvesting, may lead to an increased nighttime exposure to mosquito bites.
- Raising domestic animals near the household provides alternate blood sources forAnopheles mosquitoes, decreasing human exposure.
- War, migrations, and tourism may expose non-immuneindividuals to an environment with high malarial transmission.
The greatest risk factor for developing malaria is to live in or to visit areas where the disease is common. These include the tropical and subtropical regions of:
- Sub-Saharan Africa
- South and Southeast Asia
- Pacific Islands
- Central America and northern South America
The degree of risk depends on local malaria control, seasonal changes in malaria rates and the precautions you take to prevent mosquito bites.