Science Alert The World Health Organization warned on Tuesday a major chikungunya virus epidemic risks sweeping around the globe, calling for urgent action to prevent it.
The WHO said it was picking up exactly the same early warning signs as in a major outbreak two decades ago and wanted to prevent a repeat.
Chikungunya is a mosquito-borne viral disease that causes fever and severe joint pain, which is often debilitating. In some cases it can be deadly.
“Chikungunya is not a disease that is widely known, but it has been detected and transmitted in 119 countries globally, putting 5.6 billion people at risk,” said the WHO’s Diana Rojas Alvarez.
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She recalled how from 2004 to 2005, a major chikungunya epidemic swept across the Indian Ocean, hitting small island territories before spreading globally and affecting almost half a million people.
“Today, WHO is seeing the same pattern emerge: since the beginning of 2025, Reunion, Mayotte, and Mauritius have all reported major chikungunya outbreaks. One-third of the population of Reunion is estimated to have been infected already,” she told a press briefing in Geneva.