Travel Health: Travellers Guide to Malaria

Traveller's Guide to Malaria

By Rob Pineda (a Masters student with a special interest in parasitology)

Malaria is nasty. You don't want to get it, we don't want you to get it, so we asked Rob to explain it to us in words of one syllable. Please bear in mind though, that this is just a little light reading so that you go to your travel health assessment properly clued up.

Malaria is a serious, potentially life threatening parasitic infection transmitted by the mosquito. It's caused by four species of parasite and is one of the most significant diseases in the world. Over 300 million cases and between 700,000 and 2.4 million deaths are reported each year in affected areas. Although the brunt of this is borne by the folk that live in the malarial areas, travellers are also at serious risk if steps to prevent infection are not taken. Around 2,000 people each year enter the UK with malaria; around nine of whom will die. Many of these deaths could be prevented through following proper medical advice.

The Parasite

Female malaria-infected mosquitoes transmit malaria. In the mosquito, malaria parasites grow and develop in their guts. Infection in humans occurs when an infected mosquito bites you and takes a blood meal. While feeding on your blood, the malarial parasites pass into the blood stream, from here they infect the liver cells; multiply before bursting out of liver cells and infecting the blood cells. In the blood cells they multiply again, which causes the blood cell to burst. This releases yet more parasites which go on to infect more blood cells. This causes the fevers, which are the main symptom of malaria. These occur every 48 hours or 72 hours in one type of malaria; the time it takes for the parasites to multiply and burst blood cells.

If this sounds like your idea of fun, you're welcome to stop reading...

Symptoms

Common symptoms of uncomplicated malaria include:

High fevers Chills Headache Tiredness Severe flu-like illness

The phrase 'flu-like symptoms' can lead you to believe that malaria is less serious than is actually the case, but people with malaria are often very sick and require hospitalisation.

In complicated malaria, patients can suffer from low blood pressure, jaundice, kidney failure, coma and death. Fatalities mainly occur in one strain of the parasite known as Falciparum malaria. The distribution of this varies.

Travellers are at a higher risk of serious illness or death than the local adults in affected regions because they have no immunity to malaria whatsoever. Locals build up a degree of immunity to the parasite, making them less likely to suffer serious disease if they survive beyond childhood. Most deaths in endemic regions are in children who, like adult travellers, have no immunity. This is why it is so important for travellers to protect themselves from malarial infection.

If malaria is contracted it is treatable, in most cases in a straightforward manner, but however small there is a real risk of complications and death with any case. There is also the risk of relapse years after infection. With some species of the parasite this is true even after effective treatment.

Prevention is always better than cure.

Areas affected

Malaria occurs mostly in warmer climates and is found in tropical and sub-tropical regions, but varies between countries. On a local level, areas of high transmission occur anywhere that mosquitoes thrive, usually near areas of still or stagnant water.

Risk in individual countries varies between rural and metropolitan locations. This makes seeking advice relating to exact itinerary highly important. Changes in travel plans within a country might require further medical advice. Your local travel clinic or GP will have the latest advice on countries affected or use MASTA who have up-to-date advice.

Prevention

One of the best ways to reduce the chance of malaria infection is to reduce the chance of mosquitoes biting you.

Insect repellent (containing DEET) on areas not covered by clothes Use and properly maintain, a DEET or permethrin treated mosquito net Cover up with long sleeved clothes

Mosquito bites are most likely at around dusk and dawn, so special care should be taken to avoid bites at these times by taking the above measures or avoiding being outside at these times.

Antimalarial drugs

There is no vaccine currently available for malaria. The main method for preventing it in travellers is by taking antimalarial drugs; these prevent the infection from establishing itself, if an infected mosquito bites you. This is known as 'chemoprophylaxis' if you want to impress your friends. The type of drug will depend on where you are travelling to and your OWN medical history. Different regions have different species of malaria and different drugs are effective against them. Drug resistance is also a factor in which antimalarial you are prescribed. Drug resistance occurrs in various regions with certain drugs. The choice should always be discussed with a doctor, pharmacist or other qualified health professional. MASTA gives advice based on specific itineraries. Preventative use of antimalarial drugs is not 100% effective, so when in malaria-affected regions always remain vigilant for unexplained illness or fevers. The advice for one patient may be different from that of another patient, as the risks will be dependent on the countries visited and the medical history of the patient. This makes it important that travellers seek out individual medical consultation and advice from a GP or travel clinic.

You may have read about adverse side effects surrounding particular anti malarial drugs, such as Lariam, which have entered the media recently...

Different drugs will carry different risks of side effects for different patients (potential common side effects of individual drugs can be found on MASTA website.)

No single drug will be suitable for all patients. The side effects will be often minor compared to malaria itself. These issues should be discussed with the medical professional during consultation though. Don't be afraid to ask or question the doctor about what you have read or been told about malaria or anti-malarial drugs. Do be afraid of deciding to ignore medical advice based on a newspaper article or a fellow traveller who thinks he knows best. He doesn't, and he won't be around to help you if you end up infected with malaria.

It's important to follow medical advice. It could save your life.

Several points of advice should be emphasised about antimalarial treatment (all of which should be applied in context of the professional medical advice you recieve for the specific drugs you are prescribed).

Start treatment before you enter the country affected and follow advice dispensed with the drugs. The course must often be started several weeks before entering the region affected by malaria.

Always finish the course of treatment even after you leave the country where malaria occurs. Treatment is to carry on for up to four weeks after you leave the malaria-affected country (dependent on drug type). Stopping could lead you at risk to malaria even back in the UK. If your travel circumstances change, seek new advice.

Most of the deaths in travellers could be prevented simply by following the anti-infection measures outlined above and by following your specific medical advice (including making sure you stick to your course of antimalarials!)

Be careful of internet medical advice unless it comes from an official source

What to do if you experience any symptoms mentioned above...

If you experience any of the symptoms above while travelling, even when talking antimalarials, contact a local medical doctor as soon as possible. This applies even up to three months after return from an endemic area.

Malaria can be treated in most cases successfully without complication, but can become serious very quickly from initial onset of symptoms. Immediate medical advice should be sought if you show any of the malarial symptoms.

ALWAYS SEEK PERSONAL PROFESSIONAL MEDICAL ADVICE ON ANTIMALARIAL DRUGS AND FOLLOW IT UNLESS ADVISED NOT TO BY A HEALTH PROFESSIONAL.

More Information...

As we said earlier, this guide is really just a little light reading. If you are after in-depth professional advice on Malaria, please visit www.gapyear.com/malaria.