A Hidden Threat: Unveiling the Impact of Chikungunya in East Africa
The Painful Legacy of a Silent Crisis
In 2016, the world's attention was gripped by the Zika virus outbreak, a mosquito-borne illness that caused global panic. However, amidst this chaos, a similar yet distinct crisis was unfolding thousands of miles away in Kenya's Kilifi County.
Unraveling the Mystery: Chikungunya's Debilitating Grip
Professor George Warimwe, a dedicated scientific investigator, noticed a pattern of neurological syndromes in newborns in Kilifi. Initially suspecting Zika, the tests revealed a different culprit - Chikungunya virus. This mosquito-borne virus, first identified in Tanzania in 1952, derives its name from the Makonde language, meaning "to become contorted."
Chikungunya's symptoms are brutal - fever, severe joint pain lasting months or years, and cognitive issues in infected children. Warimwe's research team discovered that around 10% of hospitalized children with neurological illness in Kilifi were infected with Chikungunya, some just weeks old, indicating in-utero transmission.
A Decade Later: Kenya's Fight Against Chikungunya
Nearly a decade on, Kenya has intensified its efforts to combat Chikungunya with improved surveillance, testing, and mosquito tracking. Despite these measures, the country has reported over 600 cases this year, contributing to a global surge in infections.
The Global Reach of Chikungunya
The world is witnessing an unprecedented rise in Chikungunya cases. Hotspots like Brazil and India report nearly half a million infections since January, with flare-ups in the Indian Ocean islands and first-time locally acquired cases in China, New York, and Paris. European countries have also reported travel-related cases.
In Kenya, most infections this year have been recorded in Mombasa, neighboring Kilifi. However, these reports likely underestimate the true extent of the outbreak.
The Challenge of Diagnosis
Chikungunya's symptoms mimic those of malaria and dengue, leading to misdiagnoses. Clinicians are still defining the full spectrum of symptoms, and the lack of necessary diagnostics further complicates the picture.
ACHIEVE: Unlocking the Mystery
A new disease detection program, led by Warimwe and funded by CEPI, aims to bridge this knowledge gap. Medical staff at ten hospitals and clinics across Kenya and Tanzania have been trained to screen every patient with fever or neurological symptoms for Chikungunya infection.
The study, named "Accelerating CHIkungunya burden Estimation to inform Vaccine Evaluation" (ACHIEVE), receives up to $10.3 million from the Coalition for Epidemic Preparedness Innovations (CEPI). It will track the overall disease burden, Chikungunya infections in pregnant women, and mother-to-baby transmission.
For CEPI, focused on vaccine development, ACHIEVE provides vital groundwork. Understanding who is most affected and where will guide new vaccine trials and data collection. It will also inform decisions on vaccine dose distribution.
"These insights could help prioritize children and their mothers or identify other vulnerable groups at risk," explains Gabrielle Breugelmans, Director of Epidemiology and Data Science at CEPI. "Matching protection to those who need it most is our goal."
Researchers will also assess circulating Chikungunya virus strains, economic impacts on local health systems and communities, and immune responses in different age groups over time.
The Warming Climate: A Growing Concern
Over two years, ACHIEVE will assess patients with fever or neurological illness and pregnant women at delivery. This prolonged study will reveal Chikungunya's behavior and its relationship with seasonal weather changes.
"Warmer, wetter climates create ideal conditions for infected mosquitoes to expand their reach," warns Breugelmans. "Chikungunya hotspots today may not be the same tomorrow. We must stay vigilant."
The ACHIEVE study team is dedicated to alleviating the suffering caused by this debilitating illness. "Our work shows Chikungunya is common in young children," says Warimwe. "ACHIEVE will assess its spread in East Africa and provide knowledge to direct lifesaving measures where they're needed most."
The ACHIEVE study team includes scientists from the University of Oxford, University of Nairobi, Kenya Medical Research Institute (KEMRI)-Centre for Global Health Research, KEMRI-Wellcome Trust Research Programme, and the Ifakara Health Institute in Tanzania.
