UK malaria cases in returned travellers and updated guidelines

UK Health Security Agency publish malaria 2023 and 2024 (provisional) UK case numbers and updated malaria guidelines for malaria prevention in travellers from the UK

Malaria is a serious, potentially fatal, parasitic infection spread by the bite of an infected mosquito and is a risk in many tropical and subtropical countries worldwide. Malaria in the United Kingdom (UK) is a travel-associated infection, as it is not normally contracted in the UK [1].

Every year malaria deaths are reported in UK travellers who visited risk countries. The majority of UK returned travellers infected with malaria had travelled to Africa, with West Africa the most frequently visited region [2].

In 2023, a total of 2,106 malaria cases, with six deaths, were reported in UK returned travellers. This is 26% higher than numbers reported in 2022 (1,555 cases). Most 2023 malaria cases were in UK residents travelling abroad to visit friends and relatives (74%). Holiday makers accounted for 20% of cases, and people travelling for business or professional reasons, for 6%. Most cases (where travel history was known) visited Africa, particularly West Africa (69%), East Africa (11%) and Middle Africa (10%). Among malaria cases in returned UK travellers, where the history of chemoprophylaxis (antimalarial medication to prevent infection) was known; 89% had not taken chemoprophylaxis [3].

As of 3 December 2024, a total of 753 imported malaria cases have been reported in the UK between January and June 2024 [4].

On 3 December 2024, the United Kingdom Health Security Agency (UKHSA) UK Malaria Expert Advisory Group (previously known as the Advisory Committee on Malaria Prevention) published updated Malaria prevention guidelines for travellers from the UK [5].

These malaria guidelines are a practical resource for health professionals advising travellers. They may also be helpful for travellers interested in more information about malaria, including different antimalarial options. The guidelines also contain country recommendations, advice for travellers with special risks such as pregnant women and a frequently asked questions section.

All the country-specific information is also available on our individual Country Information pages.

Updates have been made to the sections on pregnancy and travellers visiting friends and relatives. Further advice regarding use of doxycycline in breastfeeding has been added: "other options are preferable in those who are breastfeeding, but doxycycline can be used if other options are unsuitable."

Malaria maps for the Central African Republic, Guyana, Nicaragua and Venezuela have been created and a new malaria map for South Africa has been produced.

Malaria map updates include:

• Eswatini map now shows a very low risk of malaria
• India map updated to show Telangana state
• Sudan map updated to show high risk of malaria and antimalarial recommendations for the whole country

Updates to country recommendations which have affected TravelHealthPro Country Information pages include:

• Pakistan: after 30th November 2024: antimalarials are no longer advised for the regions that were flooded in 2022
• Timor-Leste is recorded as having three years without malaria, so is now described as having a very low risk, although malaria has not yet been certified as eradicated in this country

All malaria deaths are preventable and imported malaria cases in the UK are strongly linked with travellers failing to follow recognised preventive measures, including not taking appropriate malaria prevention tablets (antimalarials).

Advice for travellers

Before you travel

Simple steps like using insect repellent, covering exposed skin, sleeping under treated bed nets and taking malaria prevention tablets can lower your risk of malaria.

Even if you have visited or lived in a country before, you will not have the same protection against infections as local people and are still at risk.

Get pre-travel advice as soon as possible, ideally four to six weeks before you travel, although last-minute advice is still important if time is short before you go [6].

Individual country malaria risk and prevention advice can be found on our Country Information pages and Outbreak Surveillance database.

While you are away

When visiting malaria risk areas, make sure you follow ALL these important steps for malaria prevention [5]:

Awareness of malaria risk at your destination.

• Bite prevention - avoiding mosquito bites helps reduce your risk.
• Chemoprophylaxis - take the right malaria prevention tablets* recommended for your destinations.
• Diagnosis - if you have any malaria symptoms you must get urgent medical help without delay.

*If taken as prescribed, modern prevention methods are highly effective (more than 90% protective) and can greatly reduce your risk of dying.

More advice for travellers about mosquito bite avoidance is available.

When you return

Suspected malaria is a medical emergency - some types of malaria can make you very ill and can be life-threatening.

If you or any of your family has a fever or flu-like illness after visiting a malaria risk country, you must seek immediate medical attention.

Tell your doctor or nurse that you have travelled to a country with a risk of malaria and ask for a same day result malaria test. Remember, you could still have malaria, even up to a year after a trip to a malaria-risk region [5].

Advice for health professionals

Some types of malaria can rapidly progress to severe and life-threatening illness if not treated quickly [1, 5]. Malaria must be suspected in anyone with a fever or history of fever who has returned from or previously visited a malaria risk country, regardless of whether they have taken antimalarials.

The shortest incubation period for malaria is six days. Most patients infected with the Plasmodium falciparum parasite have symptoms in the first few months after exposure and almost all within six months. Malaria infections caused by other types of the parasite may more commonly present later than six months after exposure and symptoms can be delayed for years [7].

If a traveller has symptoms and visited a malaria endemic area in the previous year, they must have an urgent blood test for malaria, with a same day result.

Information for health professionals about blood tests and how to request them in the UK is available from the UKHSA Malaria prevention guidelines for travellers from the UK (page 52) [5].

Health professionals can obtain expert advice on malaria treatment from:

• Hospital for Tropical Diseases
• Liverpool School of Tropical Medicine
• Local infectious diseases unit [6].

All malaria-positive blood tests should be confirmed by the Malaria Reference Laboratory.