Chikungunya Vaccine Availability
The first FDA-approved chikungunya vaccine (IXCHIQ) became available in November 2023, with a second vaccine candidate (PXVX0317) granted priority review in August 2024 with potential approval in 2025. 1
Current Vaccine Status
IXCHIQ (VLA1553) is a live-attenuated chikungunya vaccine that has received:
- FDA approval in November 2023 (United States)
- Health Canada approval in June 2024
- European Commission approval in July 2024 1
The second advanced candidate, PXVX0317, is a virus-like particle vaccine that:
- Received FDA priority review in August 2024
- Is under consideration for accelerated assessment by the European Medicine Agency
- Could potentially receive approval in 2025 1
Vaccine Development History
Prior to these recent approvals, no licensed vaccines or specific therapies were available against chikungunya virus. Treatment was primarily symptomatic based on clinical manifestations 2. The development of chikungunya vaccines has been ongoing since the late 1960s, with various strategies explored 3:
- Live-attenuated vaccines (like IXCHIQ)
- Virus-like particle vaccines (like PXVX0317)
- mRNA-lipid nanoparticle vaccines
- Inactivated virus vaccines
- Viral vector approaches
Prevention Strategies While Traveling
Until vaccination becomes widely available, prevention of chikungunya relies primarily on avoiding mosquito bites. The CDC recommends:
Personal protective measures:
- Using EPA-registered insect repellents containing DEET (concentration <50%)
- Wearing long-sleeved shirts and long pants when outdoors
- Using permethrin-treated clothing for additional protection 4
Environmental precautions:
- Avoiding outdoor activities during peak mosquito feeding times (dusk to dawn)
- Using screened windows and doors, air conditioning, and bed nets in accommodations 4
Clinical Considerations
Chikungunya virus infection can lead to:
- Sudden onset of high fever
- Cutaneous rash
- Myalgia
- Debilitating polyarthralgia that can persist for months to years 2, 5
While rarely fatal, the long-term arthralgia can be incapacitating, with significant economic impact, particularly in developing countries where manual labor is an economic driver 6.
Regulatory Challenges
Several regulatory pathways were considered for chikungunya vaccine approval:
- Traditional approval following demonstration of direct benefit
- Accelerated Approval pathway
- Animal Rule pathway 5
Key safety concerns that were addressed during development included:
- Potential for vaccine-associated arthralgia
- Risk of antibody-dependent enhancement of infection and disease severity 5
Future Outlook
With IXCHIQ now approved and PXVX0317 potentially following in 2025, access to chikungunya vaccines should improve globally. However, several questions remain unanswered:
- Impact of pre-existing chikungunya immunity on vaccine safety and efficacy
- Duration of protection
- Safety in children, pregnant women, and immunocompromised individuals
- Efficacy in people previously exposed to other alphaviruses 1
As chikungunya continues to spread globally, including to non-endemic areas in Europe and the Americas, vaccination will likely become an increasingly important preventive strategy 2.