Chikungunya

Advancing a chikungunya vaccine to combat a growing global health threat

Chikungunya is a viral disease transmitted to humans by infected mosquitoes. It causes fever and severe pain. The chikungunya virus was first identified in Tanzania in 1952, with sporadic outbreaks of the disease then reported across Africa and Asia. In 2004, the disease began to spread quickly, causing large-scale outbreaks around the world.

Since its re-emergence, the virus has been reported in more than 100 countries. In 2024, 620,000 chikungunya cases were reported in the Americas, Asia, Africa, and Europe.

Chikungunya is spread by the bites of infected female Aedes mosquitoes and causes fever, severe joint pain, muscle pain, headache, nausea, fatigue, and rash. Although chikungunya is not usually fatal, the resulting joint pain is often debilitating and can persist for weeks to years. People with pre-existing conditions – neonates, infants, and the elderly – may experience severe complications and death. For example, 337 confirmed chikungunya deaths were reported in Paraguay in 2023, with the majority occurring within a few months of infection.

Countries with evidence of chikungunya virus transmission to humans during the previous five years, as of 2024. Credit: United States Centers for Disease Control and Prevention

Vaccination remains the most sustainable and cost-effective solution to protect 1 billion people from chikungunya

There is no standard treatment known to cure the disease, and only two recently licensed vaccines are available for its prevention. Available treatment focuses on relieving symptoms of the disease. Because the chikungunya virus spreads through urban populations in mosquito-human cycles, transmission control relies on mosquito abatement, which is rarely effective.

Climate change could further amplify the threat posed by chikungunya. As global temperatures rise, more areas around the world will become habitable for the mosquito vectors that transmit the virus, putting more people at risk of infection.

For example, in 2007, an outbreak of chikungunya virus infections was declared for the first time in Europe with more than 200 human cases reported in Italy. In the United States, local transmission of the virus was reported in Florida, Puerto Rico, Texas, and the U.S. Virgin Islands before 2014. In 2014-2015, the virus caused intense epidemics in the Caribbean region, with rapid spread and high attack rates of chikungunya virus, followed by low circulation or detection. Since 2015, other regions of the Americas have experienced continuous and recurrent transmission. Epidemics often affect a large proportion of the population in small regions within a short time.

Accelerating a vaccine solution to prevent chikungunya worldwide

From 2020 to 2025, the International Vaccine Institute led the Global Chikungunya Vaccine Clinical Development Program (GCCDP) in partnership with Bharat Biotech and with support from the Coalition for Epidemic Preparedness Innovations (CEPI). The program advanced Bharat Biotech’s inactivated BBV87 chikungunya vaccine through a phase II/III clinical trial in Latin America and Asia to evaluate the safety and immunogenicity of a two-dose regimen. GCCDP concluded in 2025, and Bharat Biotech is leading subsequent phase III development in India.

The consortium also partnered with the United Kingdom’s National Institute for Biological Standards and Control to conduct non-human primate studies to gain additional insights on the immune response to this vaccine. The study, completed in 2022, demonstrated potent protection with Bharat Biotech’s BBV87 chikungunya vaccine through its impact on virus replication and host response to infection.

IVI also collected disease burden data and advocated for a multistakeholder approach to chikungunya vaccine development through the Uptake and Demand Assessment of a Potential Chikungunya Vaccine project, launched in 2022. This project had three key objectives:

  1. Estimate the disease burden for chikungunya at the global, regional, and national levels through a systematic review and statistical modelling.
  2. Assess stakeholders’ perceptions of chikungunya outbreak risk and the feasibility of vaccination.
  3. Initiate a multistakeholder approach by publishing an opinion editorial with global stakeholders, including CEPI and WHO, on next steps for vaccine development.

Page updated: May 2026