The UK Health Security Agency (UKHSA) has warned that parts of the UK could become suitable habitats for mosquitoes capable of spreading dengue fever, chikungunya and Zika virus by the 2040s and 2050s. The warning is based on a worst-case scenario of high emissions and a 4°C temperature rise by 2100.
The report, involving 90 experts, highlights that the Asian tiger mosquito (Aedes albopictus) could establish itself in England first, followed by Wales, Northern Ireland and parts of the Scottish Lowlands later in the century. While the mosquito only carries viruses after biting infected people, London could see regular cases of dengue fever by 2060 under this scenario.
Other projected impacts include up to 10,000 excess heat-related deaths per year by the 2050s, increased flooding, and effects on food supply and mental health. The report stresses that many risks are avoidable with swift action, including steep cuts to greenhouse gas emissions.
UKHSA already has a surveillance system with traps at borders to detect invasive mosquitoes, but this would need to be expanded. Experts advise that if mosquitoes become established, people should store water safely to prevent breeding, such as covering paddling pools and turning over buckets.
Professor Nigel Arnell of the University of Reading said it is prudent to prepare for the worst case when planning health resources. The report notes that slower warming could delay these risks by decades, but once mosquitoes arrive, their establishment is largely irreversible.
