Invasive mosquitoes which can carry the deadly dengue virus have been found breeding in homes in east London, say health chiefs.
The UK Health Security Agency raised the alarm about the discovery following the unprecedented heatwaves in the capital this year.
It has ordered enhanced surveillance and trapping activities following the detection of invasive Aedes aegypti mosquitoes and larvae at several residential properties.
Control measures have taken place to destroy the larvae.
The area of east London, which is not being disclosed by the UKHSA, is being monitored closely to identify and eradicate any further mosquitoes and larvae.
The health chiefs stressed that it is the first time that Aedes aegypti has been identified breeding in the UK.
Dr Jolyon Medlock, Head of Medical Entomology and Zoonoses Ecology at UKHSA, said: “While Aedes aegypti can transmit diseases such as dengue, chikungunya and Zika virus in countries where these infections are circulating, the risk to the public from this finding is assessed as very low.
“There is no evidence that these mosquitoes have caused human infections and importantly, to date, there is no evidence of the mosquitoes or larvae being detected in nearby public areas.”
The dengue virus can be deadly, while chikungunya and Zika can also have serious health impacts.
Dr Medlock added: “We believe these mosquitoes are accidental importations. Invasive mosquitoes can hitchhike in vehicles, baggage and imported plants, and if they find a suitable climate, can survive.
“Despite evidence of breeding in this local area and the recent heatwaves, the species is not established in the UK and cannot survive long-term in the typical UK climate, which is too cold overall.
“However, it is expected that in a warming climate, we will continue to see incursions of invasive mosquitoes, and increased reports of them being able to survive in the UK.”
It is the fourth time this species has been detected in the UK in recent years.
The latest finding was reported through UKHSA’s Mosquito Watch surveillance scheme.
The health chiefs stressed that as a “precaution” Londoners can help to reduce opportunities for all species of mosquitoes to breed by removing standing water from gardens and outdoor spaces, including water that collects in buckets, containers, paddling pools and plant pots.
Members of the public can support mosquito detection through UKHSA’s Mosquito Watch scheme and submit photographs or specimens where possible, they added.
