This page covers the side effects of Vimkunya, the chikungunya vaccine we give at Evans Pharmacy in Malvern and Claines Pharmacy in Worcester: how common each one is, how long they last, who should not have the vaccine, and why the safety concerns of 2026 applied to a different vaccine.

The common side effects

Every side effect below comes from the official product information, which pools the results of the clinical trials. The figures are for all ages combined.

Less often, between one in a hundred and one in a thousand people, trial participants reported redness or swelling at the injection site, a raised temperature, bruising, dizziness, a blocked nose or a rash. Fever itself was unusual: in the trial of people aged 12 to 64, fewer than one in a hundred had a temperature of 38°C or above.

How long do side effects last?

Briefly, for most people. In the main trial of people aged 12 to 64, both arm soreness and whole-body reactions such as tiredness or headache lasted a median of one day. In the trial of adults aged 65 and over, arm reactions lasted a median of one day and whole-body reactions a median of two days.

If a reaction is worse than you expected or lasts more than a few days, contact the clinic where you had the vaccine, and seek urgent help for any sign of a serious allergic reaction such as swelling of the face or difficulty breathing.

Older travellers usually have fewer reactions

One detail in the trial data surprises people. Adults aged 65 and over reported side effects much less often than younger adults. Pain at the injection site was reported by about 5% of older adults, and tiredness and muscle aches by about 6%, compared with roughly a quarter and a sixth of younger people. Lower reaction rates in older adults are common with many vaccines.

Can the vaccine give me chikungunya?

No. Vimkunya contains no live virus. It is made from the outer proteins of the chikungunya virus, arranged to look like the virus to your immune system, but with nothing inside that can replicate. It cannot cause the infection it protects against.

That is the key difference from the other UK chikungunya vaccine, IXCHIQ, which is a live weakened virus.

What happened with IXCHIQ, and why it is different

On 11 February 2026 the MHRA restricted IXCHIQ after a global safety review in which 28 serious adverse reactions had been reported, three of them fatal. IXCHIQ can no longer be given to anyone aged 60 or over, or to people with high blood pressure, heart disease, diabetes, chronic kidney disease or a weakened immune system. We no longer offer it.

The JCVI looked at Vimkunya at the same time and did not consider it necessary to restrict it. No safety signal has been seen. The honest caveat is that Vimkunya has not yet been used as widely as long-established travel vaccines, so it remains under close monitoring by the MHRA, as every newer vaccine is. Our guide to the chikungunya vaccine sets out the two vaccines side by side.

Questions about side effects are exactly what the consultation is for. Book your travel consultation in Malvern or book your travel consultation in Worcester.

Who should not have it

According to the product information, the only people who must not have Vimkunya are those with an allergy to one of its ingredients or who had an allergic reaction to a previous dose. The ingredients include aluminium hydroxide, sucrose and phosphate and citrate salts, and we check allergies with you before vaccinating.

We also delay vaccination if you have a high fever or are acutely unwell on the day. As with any injection, some people feel faint when it is given, so tell us if that has happened to you before. As with every vaccine, the team giving it is prepared to treat an allergic reaction straight away.

Reporting a side effect

If you think you have had a side effect from any vaccine or medicine, you can report it through the MHRA Yellow Card scheme, online or through the Yellow Card app. Reports from the public are one of the ways the monitoring of newer vaccines works. You can also tell us, and we will help you report it.

Frequently asked questions

What are the most common side effects of the chikungunya vaccine?

Pain at the injection site, tiredness, headache and muscle aches. In trials, arm pain affected about one person in four and the others about one in six each.

How long do the side effects last?

Usually around a day. In trials the median was one day for people aged 12 to 64, and two days for whole-body reactions in adults aged 65 and over.

Is the chikungunya vaccine safe?

No safety signal has been seen with Vimkunya, and the JCVI did not consider it necessary to restrict it in 2026. As a newer vaccine it remains under close monitoring by the MHRA.

Can it cause joint pain?

Joint aches were reported by fewer than one person in ten in trials and were short-lived. This is quite different from the long-lasting joint pain that chikungunya infection itself can cause.

Can I have it if I reacted badly to IXCHIQ?

Tell us about any previous reaction. The two vaccines are different products, and we assess your history at consultation before deciding.

Can I have it alongside my other travel vaccines?

Vimkunya has not been formally studied alongside other vaccines, so your pharmacist will plan the timing of your full schedule at your appointment.

Is the vaccine suitable for older adults?

Yes. It has no upper age limit, and in trials adults aged 65 and over reported fewer side effects than younger people.

What does it cost?

£180 for the single dose. For everything else about the vaccine, including who it is for and how quickly it works, see our complete chikungunya vaccine guide.