Vector-borne disease (VBD) risks in Europe

A reminder for travellers of the risk of vector-borne diseases in Europe this summer

Vector-borne diseases (VBDs) are illnesses spread by a vector, usually a blood-sucking insect or tick. These vectors can pass on a number of viruses, bacteria or parasites to humans during a blood meal [1]. Although the highest burden of these diseases lies in tropical and subtropical regions, factors such as climate change have caused several vectors to expand their range further north and into Europe. This is highlighted by guidance published by the European Centre for Disease Prevention and Control (ECDC) on 1 July 2025, regarding the changing risk of locally-acquired viral diseases spread by Aedes mosquitoes in the region [2]. The report looks particularly at dengue, chikungunya and Zika viruses and identifies 4 levels of risk in the EU/EEA recommending public health measures including surveillance, prevention and response actions. Viraemic travellers (those with viruses present in the bloodstream) arriving from endemic regions can bring these infections to Europe with them. If competent vectors (such as mosquitoes or ticks) are present and the environmental conditions are suitable this can lead to local transmission and outbreaks.

Over recent years these local outbreaks have increased in frequency and case numbers in the EU/EEA region with the ECDC report highlighting the following [2]:

• 579 locally-acquired cases of dengue fever (2010-2024) in Italy, France, Spain and Croatia. 304 of these cases were reported in 2024.
• 861 locally-acquired cases of chikungunya virus disease (2007-2024) in Italy and France.
• 3 locally-acquired cases of Zika virus disease in Var department of France in 2019.

As of 3 July 2025, at least 15 cases of locally-acquired cases of chikungunya virus disease have been reported in a number of different regions of France - see the Outbreak Surveillance page for more details.

It is important to also remember other VBDs are regularly or occasionally reported in many parts of Europe such as tick-borne encephalitis, Lyme disease, leishmaniasis, Crimean Congo haemorrhagic fever (CCHF) and West Nile fever. For further information see the 'Diseases spread by insects and ticks in Europe' factsheet.

Advice for travellers

Before you travel

Check our Country Information pages to research general health risks, prevention advice and any vaccine recommendations for your destination. Outbreaks of various VBDs will be reported on our Outbreak Surveillance database.

There is an effective vaccine to protect against tick-borne encephalitis for those visiting risk areas. See our tick-borne encephalitis factsheet for more detailed vaccine advice.

Insects and ticks are more active in Europe during warm spring, summer and early autumn months (typically May to November).

Vaccination against dengue fever is not recommended for travellers to European destinations. Joint Committee on Vaccination and Immunisation (JCVI) guidance on chikungunya vaccine use is awaited.

While you are away

Reduce your risk of insect spread illnesses, by wearing long sleeves/trousers, applying insect repellent regularly and following insect and tick bite avoidance advice.

Insect repellent should be applied after sunscreen and regularly reapplied after any activities, including swimming.

50% DEET (N, N-diethyl-m-toluamide) based insect repellents are the most effective repellents currently available and can be used in pregnancy, breastfeeding and for children from two months of age. If DEET is unsuitable, alternative insect repellents containing Icaridin (Picaridin) or Eucalyptus citriodora oil, hydrated, cyclized or 3-ethlyaminopropionate should be used.

Aedes mosquitoes bite during the day.

Anopheles and Culex mosquitoes bite in the evening and at night.

Sandflies bite at dusk and after dark and will bite during the day if disturbed.

Ticks do not jump or fly, but opportunistically grab, drop or brush onto to passing humans.

Remove ticks carefully or get medical help to remove them as soon as possible. See the UK Health Security Agency Tick Awareness leaflet for more details.

Carry a first aid kit, with appropriate over the counter medicines/cream to treat insect and tick bites.

When you return

See your GP/doctor if you experienced symptoms such as fever or rash after travelling in Europe and remember to tell them all the countries/regions you visited.

Advice for health professionals

Health professionals should be alert to the possibility of insect or tick-borne disease when consulting with an ill-returned traveller from Europe or neighbouring countries.

Health professionals who suspect a case of insect or tick-borne disease in a traveller should liaise with their local infectious disease physician, microbiologist or virologist.

The UK Health Security Agency Imported Fever Service is available to local infectious disease physicians or microbiologists. If specialist advice is needed, phone 0844 7788990.