By Dr Eddy Bajrovic*
Fewer Australians are contracting malaria overseas: Just 293 were infected already this year (2014), the lowest number by far since the peak of 966 in the year 2000.
Despite that, it’s never been more important to get expert advice if you are visiting a country with the mosquito-borne disease.
Why? Because malaria is very different to Chikungunya, dengue or Zika and some of the other more common (and generally milder) infections travellers can get from mozzies in tropical countries. Malaria can result in severe illness and death – very quickly.
So, every traveller should be clear on whether or not their itinerary is likely to put them at risk of malaria.
But, determining the malaria risk of a particular trip can be the most difficult task a doctor faces in preparing a traveller for an overseas travel.
Winning the war on malaria
As the latest World Malaria Report 2014 reveals, the face of malaria is constantly changing and the pre-travel medical advice you receive should reflect the very latest information.
Here’s a quick snapshot from the Report, just released by the World Health Organisation (WHO):
- The number of global malaria cases and deaths has fallen dramatically between 2000 and 2013. During the period, malaria fatalities decreased by 47% worldwide and by 54% in Africa, where about 90% of all malaria deaths occur. (Most Aussies are infected in Asia and Africa, and to a lesser extent in the Pacific and Latin America.)
- In 2013, there were around 198 million cases of malaria worldwide and an estimated 584,000 deaths.
- About 80% of infections occurred in just 18 countries, and a similar percentage of fatalities were in 16 countries – the vast majority being African children under 5.
- This year, 97 countries had ongoing malaria transmission and an estimated 3.2 billion people are at risk of malaria, including 1.2 billion who are at ‘high risk’ (that is, where more than one malaria case occurs per 1000 population).
Malaria decreasing in SE Asia
- In South-East Asia, the most popular holiday region with Australians, malaria occurs in 10 countries – Bangladesh, Bhutan, Democratic People's Republic of Korea, India, Indonesia, Myanmar, Nepal, Thailand, and Timor-Leste. About 1.4 billion people live under the shadow of malaria, with 352 million at high risk.
- On the plus side, the number of confirmed malaria cases reported in South-East Asia between 2000 and 2013 fell from 2.9 to 1.5 million. Three countries account for 96% of these cases – India (58%), Myanmar (22%), and Indonesia (16%). India and Thailand are on track to achieve a 50-75% decrease in cases by 2015, the Report revealed.
So, despite encouraging progress, 1.5 million cases occur in South-east Asia each year and 3 out of 4 of the region’s residents are at risk of malaria. And, so are at least some of the Aussies and other international visitors who love to holiday there.
Important malaria questions
Travellers staying in budget accommodation in malaria-infected areas are at highest risk of infection.
But, malaria doesn’t only occur ‘off the beaten track’ in rural areas: It also occurs in major cities, so people staying in upmarket accommodation can get malaria, too.
If you’re heading overseas, you need to know:
- Does the country itself have malaria?
- Is malaria a risk in the place where you will be staying (malaria is often only present in certain regions of malaria-endemic countries and not in others.)
- If so, does your length of stay, and type of accommodation or local travel, put you at higher risk of exposure.
- Is the season you’ll be travelling in a high-, moderate-, or low-risk time for malaria infection.
Get expert advice
The best way to find out if malaria will be a significant risk is NOT to ask a friend or your travel agent. Instead, take your itinerary to a doctor experienced in travel medicine, who can access the latest information and up-to-date maps.
If malaria is a risk, the doctor can advise you in regard to:
- Where and when you need to protect yourself.
- Whether malaria prevention medication is warranted or if should you rely on carrying standby treatment instead.
- Which malaria medication option is right for you. (Given you allow enough time, you can even trial one of the malaria prevention drugs to determine the one that suits you. It’s another reason to have your pre-travel medical consultation with a specialist 6 weeks before departure.)
Prevention or treatment?
Malaria is preventable and, if treated effectively and early, 100% curable. Malaria vaccines for travellers are getting closer, but for now we still rely on oral medication for both:
Prevention (chemoprophylaxis) – taken while you are still well to prevent malaria if you are bitten by an infected mosquito, and
Treatment – taken when symptoms appear and malaria is suspected or confirmed.
There are five species of malaria parasites that infect humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale, and Plasmodium knowlesi. The most common types are P. falciparum and P. vivax, with P. falciparum the most deadly.
The symptoms of malaria usually appear 8–15 days after you’ve been bitten by a mosquito infected with a malaria parasite, but sometimes not until several months later.
The first symptoms – fever, headache, chills and vomiting – may be mild (one reason why malaria is often misdiagnosed). But, if not treated within 24 hours, P. falciparum malaria can progress to a severe illness which often leads to death.
Adults frequently experience multi-organ failure, while kids with severe malaria frequently develop severe anaemia, respiratory distress, or the more severe cerebral form of the disease.
Create a head-to-toe protective barrier
Besides taking medication, it’s also important to prevent mosquito bites by:
- Applying an insect repellent containing an effective ingredient such as DEET (30-50% formulations for adults, or 10-20% formulations for young children and infants as young as 2 months of age), Picaridin, IR3535, or preparations containing extract of lemon eucalyptus oil as necessary when outdoors.
- Wearing long, loose-fitting, light-coloured clothing after dark, when malaria mozzies are active. Treating your clothing with the contact insecticide permethrin creates a deadly barrier to bugs that can bite through light material.
- Sleeping under a treated bed net, especially if you are staying in a tent or in budget accommodation without screened doors and windows, or air-conditioning. You can buy a treated net or purchase a DIY kit and use it to treat a net and clothing to give yourself a strong barrier against biting insects.
Read more about malaria and how to avoid biting insects.
*Dr Bajrovic is Medical Director of Travelvax Australia
To find out if malaria or any insect-borne diseases may be a risk at your destination call Travelvax Australia’s free travel health advisory service on 1300 360 164. You can also make an appointment to discuss and obtain medications and vaccines required or recommended for your trip.