Travelling to a tropical region is a fantastic life experience, but it isn’t without its risks. Taking preparatory measures to protect against indigenous illnesses in such areas is crucial. Among these are typhoid, dengue fever, yellow fever and of course, the focus of this post, malaria.

Those who know anything about malaria will likely have heard about its formidable symptoms (headache, fever, diarrhoea, sickness and muscular pain to name a handful), the fact that it can cause lasting health complications and, if not treated, even be fatal.

As you’ll read elsewhere on this site, the condition is transmitted by mosquito bites, and caused by a parasite (called plasmodium). There are five main types which cause the disease to occur in people, of which the P. falciparum variety is the most aggressive.

Once someone is bitten by a mosquito carrying the parasite, it spreads through the body by taking over blood cells, before eventually attacking the vital organs and central nervous system.

Generally, treatment is very effective when the infection is caught early. However, the harmful nature of the disease, combined with the likelihood that emergency health facilities may not be accessible in more remote areas, makes preventative treatment (what we term ‘prophylaxis’) essential.

No effective vaccination against malaria is available yet, although WHO states that 20 potential candidates are being assessed.

For this reason, preventative treatment is a must when visiting a malarious destination.

There are several different types of antimalarial, and the one you use depends on the area you’re visiting.

Where is malaria a risk?

Below, we’ve put together a malaria world map based on the estimated risk of malaria as defined by the US Centers for Disease Control and Prevention:

[Click to enlarge]

TREATED - Malaria Heat Map Jul 16 Proof2

(The data in this malaria world map is correct as of 7/7/16.)

It should be noted that even where the CDC state that the risk of malaria is ‘none’ (such as in Argentina) or there is no data available (Algeria) the disease may still be present in remote areas of the country. Before travel, check the NHS Fit For Travel website for specific health guidance on the destination you are visiting.

Where is malaria most common?

Using data from WHO, we compiled a list of countries where malaria is thought to be present, along with how many reported cases there were in 2014. We then used this to determine the number of cases per 100,000 people in each country:

Country Number of confirmed malaria cases in 2014* Last recorded case if nil or data not available (& number of cases)* Population** Approx cases per 100,000 CDC estimated risk***
Afghanistan 61,362   32,564,342 188.4 High
Algeria 0 2012 (55) 39,542,166 N/A No data
Angola 2,298,979   19,625,353 11714.3 High
Argentina 0 2010 (14) 43,431,886 0 None
Armenia Not available 2005 (7) 3,056,382 N/A None
Azerbaijan 0 2012 (3) 9,780,780 0 Very low
Bahamas Not available 2011 (6) 324,597 N/A None
Bangladesh 10,216   168,957,745 6 Low
Belize 19   347,369 5.5 Very low
Benin 1,044,235   10,448,647 9994 High
Bhutan 19   741,919 2.6 Very low
Bolivia 7,401   10,800,882 68.5 Low
Botswana 1,346   2,182,719 61.7 Very low
Brazil 143,415   204,259,812 70.2 Low
Burkina Faso 5,428,655   18,931,686 28675 High
Burundi 4,585,273   10,742,276 42684.4 Moderate
Cabo Verde 26   545,993 4.8 Very low
Cambodia 25,152   15,708,756 160.1 Low
Cameroon 26,651 (2013)   23,739,218 112.3 High
Central African Republic 295,088   5,391,539 5473.2 High
Chad 914,032   11,631,456 7858.3 High
China 56   1,367,485,388 0 Very low
Colombia 40,768   46,736,728 87.2 Low
Comoros 2,203   780,971 282.1 No data
Congo (Republic of the) 66,323   4,755,097 1394.8 High
Congo (Democratic Republic of the) 9,968,983   79,375,136 12559.3 Moderate
Cote d'Ivoire 3,712,831   23,295,302 15938.1 High
Djibouti 939 (2013)   828,324 113.4 No data
Dominican Republic 496   10,478,756 4.7 Low
Ecuador 241   15,868,396 1.5 Low
Egypt 22   88,487,396 0 None
El Salvador 6   6,141,350 0.1 Very low
Equatorial Guinea 20,417   740,743 2756.3 High
Eritrea 30,768   6,527,689 471.3 Moderate
Ethiopia 2,118,815   99,465,819 2130.2 Moderate
Gabon 31,900   1,705,336 1870.6 Moderate
Gambia 166,229   1,967,709 8447.8 High
Georgia 0 2009 (1) 4,931,226 0 None
Ghana 3,415,912   26,327,649 12974.6 High
Guatemala 4,931   14,918,999 33.1 Low
Guinea 660,207   11,780,162 5604.4 High
Guinea-Bissau 93,431   1,726,170 5412.6 Moderate
Guyana 12,354   735,222 1680.3 Moderate
Haiti 17,662   10,110,019 174.7 Moderate
Honduras 3,380   8,746,673 38.6 Moderate
India 1,102,205   1,251,695,584 88.1 Moderate
Indonesia 252,027   255,993,674 98.5 Moderate
Iran 358   81,824,270 0.4 Very low
Iraq 0 2008 (2) 37,056,169 0 None
Jamaica Not available 2012 (5) 2,950,210 N/A None
Kenya 2,808,931   45,925,301 6116.3 Moderate
Kyrgyzstan 0 2010 (3) 5,664,939 0 None
Laos 48,071   6,911,544 695.5 Very low
Liberia 864,204   4,195,666 20597.5 High
Madagascar 365,239   23,812,681 1533.8 Moderate
Malawi 2,905,310   17,964,697 16172.3 Moderate
Malaysia 3,147   30,513,848 10.3 Low
Mali 2,039,853   16,955,536 12030.6 High
Mauritania 15,835   3,596,702 440.3 High
Mexico 656   121,736,809 0.5 Very low
Mozambique 7,117,648   25,303,113 28129.5 Moderate
Myanmar (Burma) 152,195   56,320,206 270.2 Moderate
Namibia 15,914   2,212,307 719.3 Low
Nauru         None
Nepal 1,469   31,551,305 4.7 Low
Nicaragua 1,163   5,907,881 19.7 Low
Niger 1,953,309   18,045,729 10824.2 High
Nigeria 7,826,954   181,562,056 4310.9 High
North Korea 10,535   24,983,205 42.2 Present
Oman 0 2010 (24) 3,286,936 0 Very low
Pakistan 275,149   199,085,847 138.2 Moderate
Panama 874   3,657,024 23.9 Low
Papua New Guinea 281,182   6,672,429 4214.1 High
Paraguay 0 2011 (1) 6,783,272 0 Very low
Peru 64,676   30,444,999 212.4 Low
Philippines 4,903   100,998,376 4.9 Low
Russia Not available 2006 (102) 142,423,773 0 None
Rwanda 1,610,812   12,661,733 12721.9 Moderate
Sao Tome and Principe 1,754   194,006 904.1 Very low
Saudi Arabia 30   27,752,316 0.1 Very low
Senegal 265,624   13,975,834 1900.6 High
Sierra Leone 1,374,476   5,879,098 23379 High
Solomon Islands 18,404   622,469 2956.6 High
Somalia 11,001   10,616,380 103.6 High
South Africa 11,705   53,675,563 21.8 High
South Korea 557   49,115,196 1.1 Low
South Sudan 262,520 (2013)   12,042,910 2179.9 High
Sri Lanka 0 2012 (23) 22,053,488 0 None
Sudan 1,068,506   36,108,853 2959.1 High
Suriname 374   579,633 64.5 Moderate
Swaziland 269   1,435,613 18.7 Very low
Syria 0 2004 (1) 17,064,854 0 None
Tajikistan 2   8,191,958 0 Very low
Tanzania 680,807   51,045,882 1333.7 Moderate
Thailand 37,921   67,976,405 55.8 Low
Timor-Leste 342   1,231,116 27.8 No data
Togo 1,130,251   7,552,318 14965.6 High
Turkey 0 2009 (38) 79,414,269 0 Very low
Turkmenistan Not available 2006 (1) 5,231,422 0 None
Uganda 3,631,939   37,101,745 9789.1 High
Uzbekistan 0 2010 (3) 29,199,942 0 None
Vanuatu 982   272,264 360.7 Moderate
Venezuela 90,708   29,275,460 309.8 Low
Vietnam 15,752   94,348,835 16.7 Low
Yemen 67,513   26,737,317 252.5 Low
Zambia 4,077,547   15,066,266 27064.1 Moderate
Zimbabwe 535,931   14,229,541 3766.3 Moderate

*Data sourced from WHO

**Data sourced from CIA World Factbook

***From CDC

Burundi had the highest density of malaria cases in 2014, with nearly 4.6 million reported cases over a population of 10.7 million. In 2004, there were just 363,395 cases; meaning that Burundi had seen a 12-fold increase in reported cases over the preceding decade.

Despite being the country with the highest concentration, the CDC still only estimates the risk of malaria in Burundi as ‘moderate’; compared to several of its neighboring countries which had fewer cases per capita but are categorised as high. Really, this serves to demonstrate that risk should be taken very seriously when visiting any malarious region, be it yellow orange or red in the malaria world map provided.

Is malaria prevalence rising or falling?

Globally, malaria cases are in decline. Since 2000, WHO state that the number of cases worldwide has decreased by 37%.

But Africa has bucked this trend. Malaria prevalence is rising in several nations and the continent now accounts for almost 9 in 10 of global malaria cases.

Increasing temperatures and climate change have been cited as possible causes of the rise observed in African countries, as warmer weather enables plasmodium-carrying mosquitoes to survive at higher altitudes in these regions.

What prevention measures should I take?

When preparing for your trip, the basics are an essential requirement in addition to prophylactic medicine. Even in those areas where resistance is very low, it’s advisable to wear insect repellent (be it a spray containing an active ingredient like DEET, or a wristband), trousers and long-sleeved garments to reduce the likelihood of bites.

Sleeping under a mosquito net is essential too; make sure one is provided in your hotel room when booking.

Which antimalarial should I use?

It really depends on a number of factors, including:

  • the region you’re travelling to
  • the length of your trip
  • and your medical profile.

Many countries (and sometimes even regions within countries) may contain varieties of the parasite that are resistant to certain types of antimalarial, so it’s important to do your research first. The CDC has detailed information on where known resistance to certain drugs is present, and which drugs are the prefered method of prophylaxis.

Some treatments may also need to be commenced up to three weeks prior to travel, so it’s vital to make preparations well in advance. The closer you get to your travel date, the fewer antimalarial options you’ll have. It may be necessary to continue taking these treatments for some weeks upon your return.

The five main candidates are:

Chloroquine is one of the older antimalarials on this list and consequently one of the most susceptible to resistance. It is not generally issued as a prophylactic for the more serious form of the parasite, plasmodium falciparum, but is still sometimes useful in preventing more benign versions. For this reason, it may be more typically issued in combination with other treatment, such as proguanil, to provide comprehensive protection.

During consultation, a doctor will ask which area the patient is travelling to in order to supply the most suitable treatment.

How do they work?

Once bitten, the malaria parasite enters the body through the bloodstream then journeys to the liver. Here, the parasite replicates itself before exiting the liver to return to the bloodstream in greater numbers.

When used as a prophylactic prior to exposure, antimalarials work in the liver to destroy the parasite before it can duplicate itself and spread through the body.

However, in patients where infection has passed beyond this stage, the parasite will become more robust, necessitating urgent medical attention, and often antimalarial medicines given at higher doses. These will attack the parasite once it has re-entered the bloodstream in order to prevent it from multiplying and spreading through the body.

In summary, malaria is a condition which is much simpler to prevent than it is to treat. For this reason, it’s always better to be prepared than take the risk.

You can find out more on the above treatments, including information on possible side effects, by referring to our medicine pages.