Malaria (marsh fever, periodic fever) is a parasitic disease that involves infection of the red blood cells (RBCs). Malaria is transmitted to people by a particular type of mosquito called Anopheles, which is found mainly in tropical and sub-tropical areas. An infected Anopheles mosquito bites a person and injects the malaria parasites (microscopic organisms) into the blood. The malaria parasites then travel through the bloodstream to the liver and eventually infect the red blood cells, destroying them and releasing more parasites to attack further RBCs. In some forms of the disease, the parasites have a dormant form in the liver which can give rise to characteristic relapses of malaria

How serious is Malaria?
There are four types of malaria - the most serious type is falciparum malaria, which can be life-threatening. The other three types of malaria (vivax, malariae, and ovale) are generally a little less serious and are not immediately life-threatening.

How long does Malaria last?
The symptoms characteristic of malaria include fever, chills, muscle aches, and headache. Cycles of chills, fever, and sweating typically recur every 1, 2 or 3 days if the infection is not treated. There can sometimes be vomiting, diarrhoea, coughing and yellowing (jaundice) of the skin and the whites of the eyes.

How is Malaria treated?
Treatment for malaria depends upon the geographic area where a person has been infected with the disease because different areas of the world have malaria types that are resistant to certain medications.Drug treatment for malaria typically lasts for 7 days.

Prevention of Malarial infection
Prevention is better than cure! It is important to take sensible precautions against mosquito bites and to take medicines which will stop you catching malaria. It is very important to take medicines that reduce your risk of catching malaria (sometimes called prophylactics) if you are going to visit a country that is infected with this disease. The sort of prophylactic medicine that you need also depends on the country that you are visiting. You will need to take your medicine for a number of days before you go into the area of malarial risk, all the time you are there and for a period of time when you return. To avoid being bitten, remain indoors in a screened or air-conditioned area during the peak biting period. If out-of-doors, wear long-sleeved shirts, long pants, and hats; apply insect repellent to exposed skin.

Use insect repellents that contain DEET (diethylmethyltoluamide) for the best protection against mosquitoes and other biting insects. Follow these precautions when using repellents containing DEET:

• Read and follow the directions and precautions on the product label.

• Use only when outdoors and wash skin with soap and water after coming indoors.

• Do not breathe in, swallow, or get into the eyes. (DEET is toxic if swallowed.) If using a spray product, apply DEET to your face by spraying your hands and rubbing the product carefully over the face, avoiding eyes and mouth.

• Do not apply DEET on wounds or broken skin.

• Higher concentrations of DEET may have a longer repellent effect; however, concentrations over 50% provide no added protection.

• Timed-release DEET products may have a longer repellent effect than liquid products.

• DEET may be used on adults, children, and infants older than 2 months of age. Protect infants by using a carrier draped with mosquito netting with an elastic edge for a tight fit.

• Pregnant women should use insect repellents containing DEET, as recommended for other adults, but use sparingly. Wash off with soap and water after coming indoors.

• Children under 10 years old should not apply insect repellent themselves. Do not apply to young children's hands or around eyes and mouth.

• Travelers should also take a flying-insect spray on their trip to help clear rooms of mosquitoes. The product should contain a pyrethroid insecticide; these insecticides quickly kill flying insects, including mosquitoes.

• If you are not staying in well-screened or air-conditioned rooms, you should take additional precautions, including sleeping under mosquito nets. Bed nets sprayed with the insecticide permethrin are more effective; permethrin both repels and kills mosquitoes. In the United States, permethrin is available as a spray or liquid (e.g. Permanone™ ) to treat clothes and bed nets. Overseas, bed nets may be purchased that have already been treated with permethrin. Permethrin or another insecticide, deltamethrin , may be purchased overseas to treat bed nets and clothes.

Commonly used anti-malarial regimes
Listed below are the commonly used individual or combination regimes for prevention of malaria. This information given is for guidance only. For complete prescribing information you should read the data sheet supplied with the drugs.

	The advice given here reflects the current view in the UK. Other drug regimes may be advocated in other countries and a certain number of the drugs mentioned may not be available. You are advised to seek professional advice.
	Different drug regimes are used for different areas of the world. Thiseflects differing patterns of drug resistance. We are unable to offer precise geographical information on these pages and you are advised to seek professional advice. In the UK travellers can obtain the latest advice for their journey by following the suggested links below
	No anti-malarial drugs are 100% effective. The World Health Organisation (WHO), in their publication "International Travel and Health", state that: "All travellers should be told that protection from biting mosquitoes is their first line of defence against malaria".
	Compliance with the prescribed regime is essential. Most deaths occur to those who do not comply fully.
	Antimalarial drugs should be taken for 4 weeks after leaving the last malarious area of your journey. This will prevent the great majority of infections.
	Antimalarials are best taken after meals as this will minimise minor side effects.

Chloroquine

Chloroquine is the antimalarial drug of choice for travellers to malarious areas where there is no resistance to chloroquine. You should start taking chloroquine one week before entering the malarious area, continue during your stay and continue for 4 weeks after leaving.

UK trade names
Avloclor, Nivaquine

Dose (adults)
300mg of chloroquine base weekly. In the UK chloroquine is supplied as tablets containing 150mg of base so two tablets are taken weekly.

Common side effects
Chloroquine commonly causes minor symptoms of gastrointestinal upset usually on the day the drug is taken. These can be minimised by taking the drug after the last meal at night. Chloroquine sometimes causes headaches and may cause itching (particularly in dark skinned people). Occasionally the drug causes hair loss which is reversible and may cause temporary blurring of vision (often on the day after taking the drug).

Who should not take chloroquine?
Chloroquine should not be used by people who have epilepsy if they have had a seizure within the last 2 years or are taking anti-epileptic drugs. Chloroquine may worsen psoriasis. A reduced dose may be needed in people with renal failure.

Proguanil

Proguanil may be used as an alternative to chloroquine in malarious areas where there is no resistance to chloroquine. You should start taking proguanil one week before entering the malarious area, continue during your stay and continue for 4 weeks after leaving.

UK trade names
Paludrine

Dose (adults)
200mg of proguanil should be taken daily. In the UK proguanil is supplied as 100mg tablets so two tablets are taken daily.

Common side effects
Mild gastrointestinal upset may occur. The drug may cause mouth ulcers but this is more common when it is taken in combination with chloroquine (see below).

Who should not take proguanil?
The dose of the drug may need to be reduced in severe renal failure. Proguanil may affect the dose of anticoagulants needed for those on long term treatment. Proguanil is safe in pregnancy but a folate supplement should be used.

Chloroquine plus proguanil

This combination is used to provide protection in areas where there is limited to moderate chloroquine resistant malaria. You should start taking chloroquine and proguanil one week before entering the malarious area, continue during your stay and continue for 4 weeks after leaving.

UK trade names
Chloroquine - Avloclor, Nivaquine
Proguanil - Paludrine

Dose (adults)
300mg of chloroquine base should be taken weekly plus 200mg of proguanil should be taken daily. In the UK this means taking two tablets of chloroquine weekly and two tablets of proguanil daily.

Common side effects
See above for individual side effects. Mouth ulcers are more common with this combination than when proguanil is taken alone.

Who should not take this combination?
See above for individual contraindications.

Mefloquine

Mefloquine is an effective antimalarial for those at high risk of chloroquine resistant malaria. You should start taking mefloquine at least one week (ideally two or three weeks) before entering the malarious area, continue during your stay and continue for 4 weeks after leaving.

UK trade names
Lariam

Dose (adults)
250mg of mefloquine taken weekly. In the UK this equates to one tablet of mefloquine weekly.

Common side effects
Mefloquine is a prescription only drug and is not suitable for everybody. Its use should be discussed with your travel health adviser.
A study by MASTA and The London School of Hygiene and Tropical Medicine, published in the British Medical Journal (BMJ) shows that about 1 in 140 people taking mefloquine will experience temporarily disabling neuropsychiatric side effects. A previous study showed that very serious side effects can be expected in 1 in 10,000 people taking this drug.

Most people who get side effects will develop them after the first few doses. Some doctors will advise you to start taking mefloquine 2 or 3 weeks before you are due to leave, so that if you develop early side effects an alternative can be found. For most countries (but not all) where mefloquine is advised a suitable alternative is a combination of chloroquine and proguanil (see above). This combination will provide considerable protection against malaria although it may not be quite as protective as mefloquine.
The most common side effects with mefloquine include dizziness, headache, gastrointestinal disturbances and sleep disorders.

Who should not take mefloquine?
It is particularly important to discuss the use of mefloquine with your travel health advisor if:

	You have had fits or seizures in the past or any member of your immediate family suffers from fits or seizures.
	You have a history of psychiatric illness. Depression should be included as a psychiatric illness but only if it was bad enough to require treatment.
	You are in the first 3 months of pregnancy or you are planning to become pregnant within 3 months of stopping mefloquine.
	Mefloquine is not recommended for persons with cardiac conduction abnormalities (for example, an irregular heartbeat).
	You will be undertaking activities which require precision (for example piloting a plane, scuba diving etc.) as mefloquine can cause dizziness.

Maloprim plus chloroquine

This combination is sometimes used as an alternative to mefloquine for travellers to malarious areas in Australasia and Oceania. You should start taking Maloprim plus chloroquine one week before entering the malarious area, continue during your stay and continue for 4 weeks after leaving.

UK trade names
Maloprim - Maloprim
Chloroquine - Avloclor, Nivaquine

Dose (adults)
One tablet of Maloprim and two tablets of chloroquine should be taken weekly.

Common side effects
For chloroquine see above.
If taken at the correct dose, side effects from Maloprim are rare. It is important that no more than one tablet weekly is taken as higher doses may lead to bone marrow depression.

Who should not take Maloprim plus chloroquine?
For chloroquine see above.
Maloprim should not be used by people with an allergy to sulpha drugs. Maloprim may be used in pregnancy but a folate supplement

Doxycycline

Doxycycline is a useful alternative to mefloquine or Malarone for travellers going to areas where there are high levels of chloroquine resistance (e.g. much of Sub-Saharan Africa). Doxycycline is the preferred choice for travellers going to areas where there is significant resistance to the other commonly used antimalarials. At present this would include the border areas of Thailand with Cambodia and Burma and the western provinces of Cambodia.

Doxycycline is a useful alternative for those who cannot take other antimalarials. You should start taking doxycycline a couple of days before entering the malarious area, continue during your stay and continue for 4 weeks after leaving.

UK trade names
Vibramycin

Dose (adults)
100mg taken once daily.

Common side effects
If the contents of the capsule come into contact with the oesophagus (the tube from the mouth to the stomach) they may irritate it leading to unpleasant "heartburn" symptoms. To prevent this it is important to wash down the capsule with plenty of water. It is also wise not to lie down immediately after taking the drug (to avoid reflux).

As doxycycline is an antibiotic it may cause diarrhoea (paradoxically it will treat many causes of travellers diarrhoea) and may increase the incidence of vaginal thrush especially in those prone to this problem.
Rarely, doxycycline may sensitise the skin to the sun leading to an unpleasant rash. It is wise to use efficient sun protection screens.

Who should not take doxycycline?
Pregnant women and children

Malarone

Malarone is a combination drug containing 250mg of atovaquone and 100mg of proguanil. It has recently been licensed for the prevention of malaria by the UK authorities after large trials demonstrated that it was very effective and well tolerated. The drug is a suitable alternative to mefloquine and doxycycline for areas where there is significant chloroquine resistance (e.g. much of Sub-Saharan Africa).

At present Malarone is not licensed for trips lasting longer than 28 days. You should start Malarone 24 - 48 hrs before entering the malarious area, continue during your stay and for 7 days after leaving.

UK trade names
Malarone

Dose (adults)
1 tablet taken once daily. Malarone should be taken with food or a milky drink at the same time each day.

Common side effects
Side effects appear to be uncommon and are generally mild. In trials the most common side effects reported were headache, abdominal pain and diarrhoea. These side effects were also reported in people who were taking a placebo drug so it is difficult to decide if they were directly attributable to Malarone.

Who should not take Malarone?
There is insufficient data to recommend the use of Malarone in pregnancy or when breast-feeding. Malarone is not licensed for prevention of malaria in people who weigh less than 40kg.

Emergency standby treatment of malaria

If you are travelling to a malarious area and you may be more than 24 hours from medical attention you should consider carrying an emergency standby treatment kit. If your journey is for less than one week there is no need to take standby treatment with you as the incubation period for malaria is at least one week.

Criteria for using a standby kit
If you have been in a malarious area for at least one week and you develop a temperature of 38°C or more (use a thermometer) you should seek immediate medical attention. If you are unable to reach medical attention that day and your condition is deteriorating you should assume you have malaria and self-treat without delay.

Self-treatment should be considered to be a first-aid measure only and you should still endeavour to get to medical attention.

Suitable standby kit (adult)

	For malarious areas with no chloroquine resistance Treat with 3 tablets of Fansidar as a single dose and seek medical attention.
	For malarious areas with chloroquine resistance Treat with 600mg of quinine sulphate taken three times daily for three days followed by a single dose of 3 tablets of Fansidar after the course of quinine is finished.