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Rapid #risk #assessment, acute event of potential public health concern: #Chikungunya virus disease, #Global (#WHO, Dec. 29 '25, summary)

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By G.M.

 




Overall Risk statement

-- This RRA aims to assess the overall public health risk at the global level posed by the chikungunya virus (CHIKV) transmission during 2025, considering the criteria of potential risk for human health, the risk of geographical spread, and the risk of insufficient control capacities with available resources, and the implications for the 2026 transmission season. 

-- Chikungunya virus (CHIKV) poses a significant and growing global health risk due to large and widespread regional outbreaks in recent years, climate-driven mosquito expansion, lack of specific treatment, and increasing international travel. 

-- While mortality remains relatively low, the CHIKV infection can cause prolonged arthritis with disability as well as  severe illness in some patients. 

-- From 1 January to 10 December 2025, 502 264 CHIKV disease cases including  208 335 confirmed cases, and 186 CHIKV deaths, were reported globally. 

-- While certain WHO Regions are reporting lower case numbers compared to 2024, others are experiencing marked increases, furthermore some countries are seeing an emergence of chikungunya in previously unaffected populations. 

-- This heterogeneity in regional trends complicates the interpretation of the global situation. 

-- The data suggest localized resurgence or emergence in specific geographic areas. 

-- The region of the Americas has reported the highest number of confirmed cases followed by the European region (comprised of cases reported predominantly from French Overseas Departments in the Indian Ocean). 

-- Further, the potential for geographic spread remains substantial given that chikungunya can be introduced into new areas by infected travellers where local transmission may be established in the presence of competent Aedes mosquito, a susceptible population and favorable climatic and ecological conditions.  

-- The global public health risk posed by CHIKV transmission is assessed as moderate, driven by widespread outbreaks across multiple WHO regions during the 2025 season including areas with previously low or no transmission. 

-- The resurgence and emergence of cases in new geographic areas are facilitated by the presence of competent Aedes mosquito vectors, limited population immunity, favorable environmental conditions, and increased human mobility. 

-- The uneven distribution of cases complicates global interpretation, but highlights significant localized transmission. 

-- Control capacities remain challenged by gaps in surveillance, diagnostic access, healthcare infrastructure, and sustainable vector surveillance and control.  

-- Given the ongoing outbreaks reported globally in 2025, the potential for further spread in 2026 cannot be ruled out. 

(...)

Source: 


Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment---chikungunya-virus--global-v.1

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