Chikungunya Vaccines

Update on live-attenuated vaccine

• On May 9, 2025, FDA and CDC recommended a pause in use of the live-attenuated chikungunya vaccine (IXCHIQ) in older people following reports from several countries of serious adverse events, including hospitalizations for cardiac and neurologic events.
• On August 6, FDA lifted the pause after conducting a risk-benefit assessment and required the following changes to the vaccine's package insert:
  • Revision of the vaccine indication to be for the prevention of chikungunya in people at high risk of exposure to chikungunya virus.
  • Inclusion of statements that the vaccine is not advisable for most U.S. travelers and the decision to vaccinate should take into consideration a person's risk of severe or chronic disease outcomes if infected, of serious, severe, or prolonged chikungunya-like illness caused by vaccination, and risk of exposure to the virus.
  • Notation in the "Warnings and Precautions" section that serious adverse events have been reported during post-marketing surveillance and people aged 65 years and older with one or more chronic medical conditions might have an increased risk for these events.

Available vaccines

Two chikungunya vaccines are available in the United States:

• A live-attenuated vaccine (called IXCHIQ) that uses a weakened form of the chikungunya virus to prompt an immune response to help prevent disease.
• A virus-like particle vaccine (called VIMKUNYA) that uses a molecule that resembles the virus closely enough to prompt an immune response to help prevent illness. This vaccine does not use a live or weakened form of the chikungunya virus.

Recommendations

Keep in mind

Live-attenuated vaccine

• People with a weakened immune system or history of a severe allergic reaction to any component of the live-attenuated vaccine should not get vaccinated.
• Pregnant or breastfeeding women should discuss with a healthcare provider about the risks and benefits of the live-attenuated vaccine, compared to the risk of chikungunya illness.
• Age 65 and older is a precaution for the live-attenuated vaccine.

Virus-like particle vaccine

• People with a history of a severe allergic reaction to any component of the virus-like particle vaccine should not get vaccinated.
• Pregnant women should discuss with a healthcare provider about the risks and benefits of the virus-like particle vaccine, compared to the risk of chikungunya illness. People with weakened immune systems might not get as much protection from vaccination.

What to consider before traveling

If traveling to an area with risk for chikungunya, talk to your healthcare provider about these factors to help with your decision on vaccination:

• Symptoms of chikungunya and possible long-term joint problems after infection
• Benefits and possible side effects of vaccination
• Outbreaks or ongoing disease activity at your destination
• Duration of travel or residence, including likelihood of future travel to an area with chikungunya
• Your age (for example, older than 65 years)
• Whether you are pregnant or breastfeeding
• Underlying medical conditions that may increase your risk for severe disease (such as diabetes or heart disease)
• Conditions that may increase the risk for long-term joint pain after infection (such as joint disease)
• Your personal preferences for vaccination based on these factors