The United States is advising travellers aged 60 and up to hold off on getting the chikungunya vaccine while it looks into reports of possible side effects, including heart problems, neurological issues and even death.
The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) posted a notice on May 9 about the complications from the vaccine, which is sold under the name Ixchiq from manufacturer Valneva.
“As of May 7, 2025, 17 serious adverse events, including two that resulted in death, have been reported in individuals 62 through 89 years of age who received Ixchiq during postmarketing use globally,” the notice warned.
Health Canada, for its part, said it is monitoring the safety of Ixchiq and will take “appropriate action” if new information emerges that could change the vaccine’s benefit-risk profile.
The agency has not issued any warning against its use in older adults.
What is chikungunya?
Chikungunya is a virus spread to people through mosquito bites. It’s mostly found in parts of the Americas, Asia, and Africa, with the occasional outbreak in Europe.
The illness causes symptoms similar to dengue and Zika — most notably a high fever and severe joint pain that can be long-lasting. Other symptoms include swelling, muscle aches, headache, nausea, fatigue and a rash.
About 100 to 200 cases are reported annually among U.S. travellers.