Mosquito Watch
UKHSA scheme through which the public report invasive mosquito sightings in the UK.
A public report through Mosquito Watch, the UK Health Security Agency's mosquito-reporting scheme, led to the first Aedes aegypti colony found breeding in the UK, at homes in east London in August 2026.
Last refreshed: 4 October 2026
Timeline for Mosquito Watch
Mentioned in: Europe's West Nile cases reach 1,765
Pandemics and BiosecurityBackground
Mosquito Watch is the UK Health Security Agency's (UKHSA) public reporting scheme. People WHO find a mosquito submit photographs or specimens, which gives the agency Early Warning of invasive species.
Its most significant find came in August 2026. A report led UKHSA to Aedes aegypti mosquitoes and larvae at homes in east London, the first time the species had been found breeding in the UK. Dengue, Chikungunya, Zika and yellow fever all rely mainly on that species to spread. UKHSA destroyed the larvae, treated the site with larvicide and is monitoring the area to eradicate the colony.
UKHSA's head of medical entomology, Dr Jolyon Medlock, rated the public risk very low and found no sign that anyone had been infected. ECDC cannot yet say whether today's British climate would let the mosquito settle; it thinks the colony probably arrived with tropical plants or goods.