Zika Virus Mosquito: Aedes aegypti mosquitoes found breeding in east London

The zika virus mosquito has been found breeding in east London, but the current public-health risk is assessed as low. The species, Aedes aegypti, has not previously been recorded reproducing in the UK, and there is no evidence that the mosquitoes found have caused human infections. BBC

Aedes aegypti mosquitoes found breeding in east London

The UK Health Security Agency (UKHSA) detected Aedes aegypti mosquitoes and larvae at residential properties in east London. The species is known to transmit Zika, dengue and chikungunya in countries where those infections are circulating. This is the first time the mosquito has been found breeding in the UK, although it has been detected in the country on three previous occasions. Mirror

The discovery was reported through the UKHSA’s Mosquito Watch surveillance scheme. Measures have been put in place to destroy the larvae, while trapping and continued monitoring are being used to look for and remove any further mosquitoes or larvae in the area. BBC

The finding does not establish that Zika is circulating in London. The UKHSA said there was no evidence of human infections caused by these mosquitoes, and no evidence, to date, that the insects or larvae had been detected in nearby public areas. The reported risk to the public is therefore low. The Guardian

What the discovery means for Zika risk

Zika is mainly transmitted to people through infected mosquitoes. Reports describe the virus as usually mild for most people, but it can cause serious complications during and after pregnancy, including microcephaly, premature birth, stillbirth and pregnancy loss. Mirror

The presence of a mosquito species capable of carrying the virus does not by itself show that the virus is present in the local mosquito population. The available reporting does not establish any locally acquired Zika infection linked to the east London discovery. It does establish that the insects successfully reproduced in that local area.

The UKHSA said the species is not established in the UK and cannot survive long-term in the country’s typical climate, which it described as too cold overall. The agency nevertheless expects further incursions of invasive mosquitoes and more reports of them surviving in the UK as the climate warms. The Guardian

How the mosquitoes may have arrived

Reports say Aedes aegypti is normally found in tropical and subtropical climates. The UKHSA said invasive mosquitoes can be accidentally transported in vehicles, baggage and imported plants. The east London discovery followed recent heatwaves, but the agency said the wider UK climate remains unsuitable for the species to persist long-term. BBC

Residents have been advised to remove standing water from gardens and outdoor spaces, including buckets, containers, paddling pools and plant pots, because these can provide places for mosquitoes to breed. The immediate response remains focused on destroying larvae and checking whether any further insects are present. The Guardian