Chikungunya vaccination information

Chikungunya vaccinations authorised in the UK including updates on recent possible serious adverse events in older people and JCVI advice

• This updates the news item of 25 July 2025

Chikungunya is a viral infection predominantly spread to humans through the bite of an infected Aedes mosquito. The Aedes mosquito bites during the day and is found widely throughout the world. In recent decades, following international spread, chikungunya virus (CHIKV) has become a major global health problem [1].

Chikungunya is an unpleasant disease but is rarely fatal. Symptoms include:

• severe joint pains (arthralgia) and muscle pains (myalgia)
• headaches
• sensitivity to light (photophobia)
• skin rashes

The symptoms usually improve within 1–2 weeks, but the joint pains can be severe and may persist for months or even years.

Two new vaccines have recently been approved for use in the UK, the European Union, and the USA. IXCHIQ^® is a live vaccine, approved in the UK on 5 February 2025, for individuals 18 years and older*. Vimkunya^® is a virus like particle vaccine, approved in the UK on 1 May 2025, for individuals 12 years and older.

*See JCVI advice on age groups for the vaccine below

IXCHIQ^® and Vimkunya^® vaccines have been reviewed by the Joint Committee on Vaccination and Immunisation (JCVI) and guidance will be drafted for the UK Health Security Agency 'green book' Immunisation against infectious disease.

Health professionals offering these vaccines must ensure they are adequately informed on their use.

In early March 2024, the U.S. Centres for Disease Control and Prevention (CDC) announced it was investigating five hospitalisations involving cardiac and neurologic events among older people following receipt of the IXCHIQ^® vaccine [2].

In addition, on 25 April 2025, the French National Authority for Health (HAS) revised its recommendations and suspended IXCHIQ^® use in individuals aged 65 years and older pending further evaluation. This was following reports of three serious adverse events in individuals over 80 years old with significant pre-existing comorbidities. Two of these individuals experienced symptoms similar to those of a severe form of chikungunya a few days after vaccination; one died. The third was discharged from hospital. These cases were reported via the French pharmacovigilance system [3, 4].

As of 7 May 2025, the U.S. CDC and Food and Drug Administration (FDA) reported 17 serious adverse events, including two deaths, in individuals 62 to 89 years of age. Six of these reports have been from the U.S. [5]. Many of the people affected also had other illnesses and the exact cause of these adverse events and their relationship with the vaccine have not yet been determined [5, 6]. In light of these events, the U.S. CDC and FDA recommended a pause in the use of IXCHIQ^® in individuals 60 years of age and older while post marketing safety reports are investigated [5].

On 9 June 2025, the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK put a temporary restriction on IXCHIQ^® vaccine in people aged 65 and over whilst a further safety review is conducted. A total of 23 serious adverse events have now been reported globally following vaccination [7].

On 11 July 2025, the European Medicines Agency (EMA) announced their Pharmacovigilance Risk Assessment Committee (PRAC) had completed a safety review and a previous temporary restriction on the use of IXCHIQ^® in individuals aged 65 years and over will be lifted. PRAC concluded that the vaccine should only be given when there is a significant risk of chikungunya infection and after careful considerations of the risks and benefits of vaccination [8].

On the 6 August 2025, the FDA removed the pause in the use of IXCHIQ^® in individuals 60 years of age and older following an updated benefit-risk assessment in this age group [9].

On 16 July 2025, Joint Committee on Vaccination and Immunisation (JCVI) published advice on the use of chikungunya vaccines in the UK [10].

JCVI has considered these reports as part of their review. In addition to bite avoidance measures, chikungunya vaccine may be considered for:

• those travelling to regions with active CHIKV outbreaks
• long term or frequent travellers to regions with CHIKV transmission in the past 5 years*
• laboratory staff working with CHIKV

*See advice for health professionals below

When vaccination is considered to be indicated, JCVI advises:

• Vimkunya^® vaccine may be offered to individuals aged 12 years old and over
• IXCHIQ^® vaccine may be offered to immunocompetent individuals aged 18 to 59 years old

Currently there is no evidence of a safety signal with the use of Vimkunya^® in older adults. The JCVI did not consider it necessary to restrict the use of Vimkunya^® at this time, but note that this vaccine has not been used extensively [8].

Advice for travellers

Before you travel

Check our Country Information pages to research general health risks, prevention advice and any vaccine recommendations or malaria advice for your destination. Regional information about biting insects that transmit infections is available on our Country Information pages 'Other Risks' section. Outbreaks of chikungunya will be reported in our Outbreak Surveillance section.

Make an appointment with your GP, practice nurse, a travel clinic or a pharmacy offering travel service. They can advise you on the most suitable preventive measures for your trip.

While you are away

As many insect and mosquito infections are spread by day-biting mosquitoes, take particular care with bite avoidance especially around dawn and dusk.

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.

See mosquito bite avoidance for travellers for more advice.

If possible natural or man-made water filled containers, which may act as mosquito-breeding sites, should be removed.

When you return

If you have symptoms like a high fever, severe joint pains, muscle pains, headaches, sensitivity to light or skin rashes get urgent medical advice. Remember to tell your treating health care professional where you have visited.

Advice for health professionals

Health professionals advising travellers can check our Country Information pages for vaccine recommendations, malaria guidance and specific risk advice. UK Health Security Agency and NaTHNaC have reviewed chikungunya epidemiology and the updated recommendations for individual countries are available on the Country Information pages.

Health professionals who suspect a mosquito or insect spread infection such as chikungunya in a recently returned traveller, should discuss this urgently with their local microbiology, virology or infectious diseases consultant. A full travel/clinical history will need to be provided. They may advise that appropriate samples are sent for testing to specialist laboratory facilities at the Rare and imported pathogens laboratory (RIPL) in the UK.