Scientists launch largest-ever study tracking chikungunya burden in East Africa

OSLO/ OXFORD, UK, 12 Dec 2024—A team of scientists in the UK, Kenya and Tanzania will soon find out the extent to which chikungunya, a debilitating mosquito-borne disease causing large outbreaks in Asia and South America, is also affecting countries in East Africa.

Led by the University of Oxford, the scientists are set to investigate the number of children and adults affected by chikungunya at sites in Kenya and Tanzania. 

Chikungunya is typically characterised by fever and severe joint pain, which is often debilitating and can last for weeks, months or even years, severely impacting quality of life. Other symptoms include muscle pain, headache, nausea, fatigue, and rash. Some populations, such as children and pregnant women, are at higher risk of severe disease and death.

While chikungunya outbreaks are occurring with increasing regularity around the world—with over 480,000 cases reported this year globally—testing remains largely limited in East Africa and there is concern that cases are largely going unreported.

From early Spring 2025, all patients, including children, presenting at ten healthcare facilities across the two countries with fever or neurological symptoms will therefore now be screened and tested for chikungunya virus. 

The new research—known as the Accelerating CHIkungunya burden Estimation to inform Vaccine Evaluation (ACHIEVE) study—will be supported by USD 10.3 million (GBP 7.9 million) funding from the Coalition for Epidemic Preparedness Innovations (CEPI). 

The ACHIEVE study team—which includes scientists at the University of Oxford, University of Nairobi, the Kenya Medical Research Institute (KEMRI)-Centre for Global Health Research, the KEMRI-Wellcome Trust Research Programme and the Ifakara Health Institute in Tanzania—will collect this information over the next three years to better estimate the number of people with chikungunya in the region and inform outbreak planning efforts.

Professor George Warimwe, Lead of the ACHIEVE study and Professor of Vaccinology at the University of Oxford, said “We lack good estimates of the burden of chikungunya in East Africa, and the clinical manifestations of disease are not well characterised, especially in children. This investment is an important step towards improving our understanding of chikungunya in the region that will ultimately inform disease control strategies.” 

The study will also provide important data to advance the development of a vaccine against chikungunya. The first-ever chikungunya vaccine—developed by French pharmaceutical company Valneva with support from CEPI and the European Commission—was licensed last year in the US and has since been approved in Canada and the European Union. CEPI and partners are now working to accelerate access to the vaccines in outbreak-affected regions who are most at risk from the disease, such as East Africa.

“Having better insights into chikungunya’s prevalence and its associated symptoms will be crucial in  guiding the design and implementation of future vaccine trials and vaccination programmes in affected countries” explains Dr Gabrielle Breugelmans, Director of Epidemiology and Data Science, CEPI. 

“Understanding at-risk groups in East Africa will also help determine the necessary number of chikungunya vaccine doses to be included in global stockpiles for potential future deployment. Additionally, these insights will enable the development of targeted deployment strategies tailored to different locations, based on the varying epidemiological patterns.”

The ACHIEVE study research team will also look at other important research areas including:

• the prevalence of chikungunya among pregnant women which may lead to mother-to-child virus transmission. 
• the economic burden associated with chikungunya on local health systems and communities.
• the diversity of chikungunya virus strains in the region which could help to improve understanding of the range of viral mutations that vaccines should be targeting.

ACHIEVE forms part of CEPI and the University of Oxford’s strategic partnership launched in 2023 to advance preparedness against known and novel infectious disease threats. 

ENDS

About the ACHIEVE study

• ACHIEVE will be conducted in Kigoma and Tanga in Tanzania and Siaya, Kilifi and Isiolo in Kenya.
• Results from the research will be shared in open access journals to ensure that the whole public health community can benefit from the research.

About Chikungunya

Chikungunya is a mosquito-borne disease belonging to the Togavirus family. It is commonly transmitted by female Aedes aegypti and Aedes albopictus mosquitoes. The name chikungunya derives from a word in the Kimakonde language, meaning “to become contorted”.

Chikungunya symptoms are typically characterised by fever and severe joint pain, which is often debilitating and can last for weeks, months or even years, severely impacting quality of life. Other symptoms include muscle pain, headache, nausea, fatigue, and rash. Some populations are at higher risk of severe disease and death.

Chikungunya was first identified in Tanzania in 1952 and has since become widely distributed across the globe. 

Since 2004, the disease has spread quickly causing large-scale outbreaks around the world.  Today, over a billion people live in areas where Chikungunya is endemic. Climate change could further amplify the threat posed by Chikungunya by making more regions habitable for the mosquito vectors that transmit the virus, increasing the size of the population at risk of infection.

CEPI’s response to Chikungunya

CEPI’s aim is to advance Chikungunya candidate vaccines towards licensure and enable equitable access for populations living in affected countries. CEPI has supported three Chikungunya vaccine candidates in late-stage development, committing up to US$101 million in funding with support from the European Union’s Horizon programme. Two of these candidates—developed by Valneva and IVI & Bharat Biotech—remain in active development. Valneva’s Chikungunya vaccine is the first in the world to be approved by a Stringent Regulatory Authority. CEPI and its partners are now working to expand access to the vaccine in outbreak-affected countries, including supporting scientific studies to generate additional data to help the rollout of the vaccine in endemic countries and for potential label extensions to expand access to vulnerable populations at risk of infection.

About CEPI 

CEPI is an innovative partnership between public, private, philanthropic and civil organisations. Its mission is to accelerate the development of vaccines and other biologic countermeasures against epidemic and pandemic threats so they can be accessible to all people in need. CEPI has supported the development of more than 50 vaccine candidates or platform technologies against multiple known high-risk pathogens or a future Disease X. Central to CEPI’s pandemic-beating five-year plan for 2022-2026 is the ‘100 Days Mission’ to compress the time taken to develop safe, effective, globally accessible vaccines against new threats to just 100 days.

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the eighth year running, and number 3 in the QS World Rankings 2025. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer. Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions.