A recent groundbreaking study by researchers at the UK Centre for Ecology & Hydrology (UKCEH) has projected a significantly expanded risk landscape for chikungunya virus transmission across Europe. Contrary to previous assumptions that limited virus spread to warmer climates, this research uncovers the virus’s ability to proliferate at temperatures as low as 13 degrees Celsius. This revelation signals a more extensive and prolonged period of vulnerability to chikungunya outbreaks, especially considering the establishment and northward expansion of the Asian tiger mosquito, Aedes albopictus, a primary vector of the disease.
This mosquito species, renowned for its adaptability and invasive nature, has become entrenched in warmer European regions and is now inching closer to the UK’s borders. The team’s risk mapping delineates transmission danger zones by analyzing 10km squared regions, pinpointing areas where the tiger mosquito thrives and where the climate permits viral incubation and spread. The resultant maps reveal that the virus’s transmission window spans several months annually in southern and southeastern Europe, with particularly high risk documented in nations like Spain, Portugal, Malta, and extending marginally into southern England.
Surveillance data emphasizes an alarming surge in the number of chikungunya cases within Europe, with record-setting outbreaks reported in France and Italy throughout 2025. This upward trend correlates directly with the range expansion of Aedes albopictus, a vector not only for chikungunya but also dengue and Zika viruses. While southern England currently experiences sporadic mosquito detections without established populations, this study forewarns of a potential establishment fueled by rising temperatures and environmental shifts, particularly in southeast England.
Crucially, previous studies posited a higher thermal minimum between 16 to 18 degrees Celsius for chikungunya virus replication and transmission by Aedes albopictus. The new study’s identification of a reduced threshold near 13-14 degrees Celsius significantly reshapes the understanding of climate suitability for viral incubation within the mosquito. This adaptation implies that viral replication cycles and subsequent transmission risks can persist during cooler months and in more northern latitudes than once believed, thereby extending the seasonal transmission dynamics.
Sandeep Tegar, lead epidemiological modeller at UKCEH, underscores the rapid climatic warming trends in Europe, which facilitate the tiger mosquito’s expansion into temperate zones previously inhospitable to it. The lowered temperature transmission threshold implies a broadening geographical risk footprint and extended temporal windows for chikungunya virus spread. This has imminent implications for public health authorities, which can leverage these refined risk assessments to enhance localized vector control interventions and deploy health resources effectively during predicted peak transmission periods.
The interplay between globalized transportation networks and climate change intensifies risks by enabling the tiger mosquito’s propagation beyond its native range. International travel has repeatedly acted as a conduit for infected individuals to transport the virus, with local Aedes albopictus populations then facilitating subsequent human-to-human viral spread. This dynamic was evidenced by a record 73 travel-associated chikungunya cases in the UK during the first half of 2025 alone, a stark increase from prior years, demonstrating the critical need for focused mosquito surveillance coupled with traveler health monitoring.
The UKCEH risk maps present a sobering insight: although chikungunya transmission in most of the UK remains low, localized risk exists, especially in East Anglia and the southeastern coast during July and August, with sporadic vulnerability in other southern pockets. As environmental changes proceed, these zones may expand, necessitating heightened vigilance. Dr. Steven White, co-author of the study, stresses the importance of preemptive measures to prevent the tiger mosquito from taking hold in the UK, owing to its competency in spreading several debilitating arboviruses, including chikungunya, dengue, and Zika.
Beyond detection, mitigation strategies emphasized in the study include meticulously monitoring and eliminating mosquito breeding sites such as stagnant water collections, deploying targeted fumigation efforts, and raising public awareness about preventive behaviors against mosquito bites. The UK Health Security Agency’s national surveillance framework, prioritizing high-risk entry points like airports and ferry terminals, operates as a frontline defense in identifying early invasions of the tiger mosquito.
Importantly, this study embodies a paradigm shift in assessing vector-borne disease threats under climate change. The lowered threshold augurs not only an extended presence of vector mosquitoes but also accelerated virus replication speeds at suboptimal temperatures. This phenomenon potentially amplifies transmission efficacy and outbreak scale, underscoring the urgency of integrating climate projections with vector ecology and pathogen biology in epidemiological modeling.
Furthermore, UKCEH’s approach to geospatial risk analysis sets a precedent for exploring other vector-borne diseases. Their recent production of a dengue fever risk map for Europe and plans to address Zika and West Nile virus transmission patterns reflect an integrated strategy to confront emerging infectious diseases in a warming world. Continuous refinement of these models is imperative, given the dynamic feedback between environment, vector behavior, and viral evolution.
In summary, the comprehensive findings presented by UKCEH researchers illuminate an expanded temporal and geographical risk for chikungunya virus transmission in Europe, catalyzed by reduced temperature constraints and an advancing mosquito vector. This serves as both a call to action for enhanced surveillance and vector management and a critical alert regarding the broader impacts of climate change on infectious disease dynamics in temperate regions.
Subject of Research: Temperature-sensitive incubation, transmissibility, and the geographic risk of Aedes albopictus-borne chikungunya virus in Europe.
Article Title: Temperature-sensitive incubation, transmissibility, and risk of Aedes albopictus-borne chikungunya virus in Europe.
News Publication Date: 18 February 2026.
Web References:
- DOI: https://doi.org/10.1098/rsif.2025.0707
- UK Centre for Ecology & Hydrology: https://www.ceh.ac.uk/
References:
Tegar et al. 2026. Temperature-sensitive incubation, transmissibility, and risk of Aedes albopictus-borne chikungunya virus in Europe. Journal of Royal Society Interface. DOI: 10.1098/rsif.2025.0707.
Image Credits: Journal of Royal Society Interface.
Keywords: Disease outbreaks, Invasive species, Climate change, Mosquitos, Viruses, Tropical diseases, Disease control, Epidemiology.
