Contagious Diseases Series: Malaria

Malaria is a serious disease and, in some cases, can prove fatal.

The World Health Organisation estimates that in 2017, there were 219 million cases of malaria worldwide.  In that year, Malaria caused 435,000 deaths.

Malaria is caused by a parasite called Plasmodium that commonly infects certain types of mosquitoes which in turn bite humans.  There are five species of Plasmodium:

  • Plasmodium vivax
  • Plasmodium falciparum
  • Plasmodium malariae
  • Plasmodium ovale
  • Plasmodium knowlesi

Of these five species, Plasmodium falciparum is the most severe and can be fatal in up to 10% of cases.  Most at risk are pregnant women and children.  The other four species are less severe but can also lead to death.

How do you get it?

Malaria is generally transmitted by infected female Anopheles mosquitoes.  Once a mosquito is infected with the parasite, it remains infectious for its lifetime.  It is also possible for a mosquito that bites an infected person to become infected and then pass it to other people.

Once a person has been bitten, the parasite travels through their bloodstream to the liver where it multiplies.  The parasites ultimately leave the liver and enter red blood cells where they grow and burst the cells.  This allows the parasites to move to other blood cells.  While doing this, the parasites release toxins into the bloodstream which cause you to feel unwell.

Cases of infection following blood transfusion have also been reported.  This is one of the reasons why it is recommended people who have travelled to countries where Malaria is prevalent delay giving blood for a short period following their return home.

Malaria cannot be transmitted from human to human – to contract it, you must be bitten by an infected mosquito.

Where in the world is it?

Malaria is common in tropical and sub-tropical areas.  Most notably, it is found in Asia, the Pacific Islands, Africa, parts of the Middle East, Central and Southern America.

Australia is Malaria-free but it is occasionally found in the Torres Strait Islands.

What are the symptoms?

Typically it takes 7-14 days for an infected person to feel unwell but it can also take up to 4 weeks for symptoms to manifest.  In some instances, symptoms can re-occur months or years post-exposure.  This is because some parasites can remain dormant in the liver for up to 4 years.

The most common symptoms include:

  • Fever which may either come and go or be constant
  • Headache
  • Excessive sweating
  • Shivering / chills
  • Nausea
  • Vomiting
  • Joint and muscle pain
  • Diarrhoea
  • General malaise (feeling unwell)
  • Fatigue
  • Abdominal pain
  • Cough
  • Anaemia and jaundice

How is it diagnosed and what is the treatment?

Diagnosis usually involves clinical assessment where a doctor will examine you, discuss your symptoms and medical history.  The doctor will also order a blood test to confirm the diagnosis.  This blood test will detect the presence of malarial parasites in your blood.

A single positive blood test result proves infection with Malaria.  A single negative blood test result does not though prove that you do not have it.  To be conclusive, you will need to return at least 3 negative blood test results to be sure you don’t have the disease.

Treatment usually involves prescription medication.  The type of medicine prescribed will depend on the type of Malaria you have.  Treatment should be started as soon as possible to improve the likelihood of a swift recovery.  If you have been to countries where Malaria is prevalent and you think you may have contracted it, seek urgent medical attention.

How can you minimise the risk of contracting it?

Fortunately, there is anti-malarial medication available to minimise the risk of infection while travelling.  If you are travelling to an area where the disease is prevalent, visit your GP 4-6 weeks before departure to see if you are a candidate for prophylactic medication.

If you decide to take anti-malarial medication, make sure you do so as prescribed.  This is very important.  You will need to take medication before you travel to the affected area, while you are there and also after you leave.  This could involve continuing the medication for up to 4 weeks after you have left the affected region.

Taking anti-malarial medication is not a guarantee that you will not be infected.  It is also important that you take other preventive measures to minimise the risk of being bitten.   Anopheles mosquitoes tend to be most active at dawn and dusk but you can still be bitten at other times of the day or night.

Here are our top tips to help minimise the potential of infection if travelling to high risk areas:

  • Cover as much exposed skin as possible at all times – day and night. Preferably wear socks with closed in shoes and wear light coloured long sleeve shirts and long pants.
  • Stay and sleep in accommodation which has fly screens on the windows or air conditioning.
  • Use mosquito nets if you cannot secure your room against mosquitoes or are sleeping outside.
  • If safe to do so, use mosquito coils and/or plug in repellent devices.
  • Use insect repellent that contains DEET or picaridin.
  • Apply insect repellent in the morning and make sure you re-apply it frequently.
  • If using sunscreen, apply repellent after you apply your sunscreen.
  • Stay indoors when mosquitoes are particularly active.
  • Mosquitoes breed in containers and junk so don’t allow water to pond or collect around your accommodation. Mosquitoes breed in still water (eg pot plant bases, coconut shells, tyres, containers such as vases, tubs and buckets).

Many travellers will be exposed to infected Anopheles mosquitoes will travelling.  Fortunately there are measures you can take to minimise the risk of infection.  If you do suffer the misfortune of contracting Malaria – or think you may have – seek medical attention as soon as possible.  Early detection will increase the chance of a quick recovery.

Got questions about Malaria and travel insurance?  Why not call us on 1300 819 888 or send an email to