This factsheet is for people who have malaria, or who would like information about it.
Malaria is an infectious disease commonly found in tropical areas such as sub-Saharan Africa, Central and South America, the Indian subcontinent, South East Asia and the Pacific Islands (these are known as malarious regions). It's caused by a parasite called Plasmodium, which is passed to people through bites from mosquitoes carrying the parasite.
There are two categories of malaria.
Around 1,500 people a year in the UK get infected with malaria when abroad.
The first symptoms of malaria are like having the flu. You may have:
A day or so later, you may get a fever. Some people have malaria attacks – these have three stages: shivering, hotness and sweating.
Symptoms can appear any time from a week to 14 days after you’re bitten by a mosquito carrying the malaria parasite. The time it takes your symptoms to appear (the incubation period) can vary depending on the type of parasite that the mosquito was carrying, whether or not you have partial immunity or if you have taken any anti-malaria tablets.
If you have an illness with a fever and have travelled to a region with malaria within the last year, visit your GP. You can still catch malaria even if you have taken antimalarial medicines correctly.
If you are infected with P. falciparum, malaria can progress to a more severe form (also called complicated malaria). Complications can affect your brain, kidneys, blood and lungs. They can develop within hours or days of your first symptoms and can be fatal within 24 hours.
Symptoms of severe malaria can include:
It's important to seek urgent medical attention if you suspect you have severe malaria. Always tell your doctor where you have travelled. Complications are likely to be more severe in pregnant women, children, older people and people who have a weakened immune system, such as those who have HIV/AIDS.
Malaria is caused by an infection with a parasite called Plasmodium that is passed to people through mosquito bites.
You can catch malaria if a female anopheles mosquito bites someone carrying the malaria parasite and then bites you, passing the parasite on to you.
There are four main types of Plasmodium parasite that infect humans.
About eight in 10 UK travellers who get malaria are infected with P. falciparum. Most of the other people are infected by P. vivax, and just a few are infected with the other two species. You can get infected with more than one type of Plasmodium parasite. Each parasite causes a slightly different type of illness.
The malaria parasite passes through your blood into your liver, where it grows and develops.
After it has completed its development, it travels back into your bloodstream and eventually attacks your red blood cells, which you need to carry oxygen around your body. You will then get symptoms of malaria.
Your GP will ask about your symptoms and examine you. He or she may also ask you about your medical history and which countries or regions you have visited within the last year, including any stopovers.
Malaria is a medical emergency. If your GP suspects that you have malaria, he or she may refer you to your local hospital to have a blood test to confirm if you have malaria parasites in your blood and what type of parasite you have been infected with. You will need to have at least three blood tests over one to three days as the levels of malaria parasite in your blood can vary. For example, if you have taken antimalarial medicines, the levels of parasite may be too low to detect. If you are still taking antimalarial medicines while being investigated, your doctor may ask you to stop these so that they don’t interfere with any blood tests you may have. Repeating blood tests can help to confirm if you have malaria.
If you’re diagnosed with malaria, your doctor will notify the public health authorities. It’s also important for you to let any travel companions know to ensure they get tested too. They may also be infected but not know as he or she may not develop any symptoms for some time.
There are a number of medicines that can treat malaria but you must start your treatment as soon as possible. Certain medicines don't work for malaria from some parts of the world – your doctor will ask where you have been and take this into account.
Some malaria medicines are also used to help prevent the infection. But if you have taken a medicine to prevent malaria, you can't take the same one again to treat it. So it's important to tell your doctor about any antimalarial medicines you have taken – take the medicine packaging to your GP appointment if you can.
Treating mild P. falciparum malaria
There are three main treatments for mild P. falciparum malaria.
The standard treatment for mild P. falciparum malaria in the UK is quinine tablets followed by a second medicine, which may be:
Alternative medicines for P. falciparum malaria include:
If you have P. falciparum malaria, you will usually need to stay in hospital to be monitored. This is because malaria can rapidly progress to a more severe infection.
Treating severe P. falciparum malaria
The standard treatment for severe P. falciparum malaria is quinine, which will be injected directly into a your bloodstream through a vein (intravenously). An alternative treatment is artesunate. Once you're well enough, you can have the rest of your treatment as tablets that you swallow.
If you have severe P. falciparum malaria, you need to be monitored carefully and treated for any complications. The severity of malaria usually depends on how many of your red blood cells are infected.
Treating other types of malaria
The standard treatment for other types of malaria is chloroquine tablets (eg Avloclor, Malarivon, Nivaquine). You can take chloroquine if you're pregnant.
If you have malaria caused by P. vivax and P. ovale, you will need treatment to stop the infection coming back because parasites can stay in your liver. Primaquine is the usual medicine. If you’re pregnant, your doctor will usually advise that you wait until you have given birth before you take this.
If your illness is mild, you will probably be able to take your medicines at home. However, you will need to go to hospital if you develop complications or need medication through an intravenous drip.
If you’re diagnosed with severe malaria your doctors will monitor your kidneys, blood pressure, fluid balance (how much you drink and how much urine you pass), and your blood sugar levels as well as treat any complications. For example, you may be given a glucose drip to help raise your blood sugar levels if they drop.
If you're born in an area with malaria, you may develop a form of immunity to the infection. It never gives complete protection but it can reduce your risk of developing severe malaria. However, if you leave the area for six months or more you may lose this immunity so you will need to take antimalarial medicines if you return or go to another area with malaria.
Complications of malaria are more likely if you’re pregnant. Malaria in pregnancy is also associated with miscarriages or stillbirths.
If you have malaria and are pregnant, you will need to take quinine. Scientific evidence shows that quinine is safe in pregnancy, although it can increase the risk of you having low blood sugar levels. Your doctor will monitor you and your baby for any signs of complications. He or she may decide you need to have your baby early if this is the safest option for you and your baby.
For answers to frequently asked questions on this topic, see Common questions.
For sources and links to further information, see Resources.
This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.
Produced by Stephanie Hughes, Bupa Health Information Team, February 2012.