Disease-carrying bugs from Europe are increasingly crossing the Channel and arriving in Britain as a result of climate change, government scientists have warned.
Insects that once only survived in the warmer climes of the Mediterranean or further south are now migrating to northern Europe. They are then blown over the Channel on the wind or hitch a lift on ferries or trains.
Studies show that the pests are now also able to flourish in the UK as temperatures rise and winters become less intense.
The Government’s leading in-house experts are dedicating millions of pounds of taxpayer money to tackling the issue of foreign species landing in the UK.
Plant, animal and human health scientists are all grappling with the same issue and the UK Health Security Agency (UKHSA) is increasingly alarmed at the prospect of dengue fever (better known as break-bone fever) carried by the tiger mosquito. Cases are rising in northern France, with evidence suggesting it is becoming entrenched in the area.
Models predict that much of the UK will be hospitable to this mosquito in coming years as a result of climate change.
Last year, Dr Jolyon Medlock, the head of medical entomology and zoonoses ecology at the UK Health Security Agency (UKHSA), said the tiger mosquito could be embedded in the UK within less than a decade.
Dr Isabel Oliver, the chief scientific officer at UKHSA, told The Telegraph: “The majority of illness and deaths caused by mosquito-borne diseases occur in the tropics. However, there is an increasing risk posed by mosquitoes invasive to the UK.
“Factors behind this increasing risk include climate and environmental change, the globalisation of travel and trade as well as changes in land use.”
The UKHSA runs a surveillance scheme with a range of traps in Kent, Sussex and elsewhere in the south of England which are regularly checked by entomologists for signs of the tiger mosquito (Aedes aegypti).
“As well as monitoring infections in people, the UK Health Security Agency undertakes surveillance of mosquitoes and other vectors of infection to monitor risks to the health of the population so we can identify any changes promptly and effectively,” Dr Oliver added.
Tick-borne encephalitis and Lyme disease are also being watched closely by public health experts as they head to the UK from abroad, along with West Nile virus, chikungunya virus and malaria.
‘We can’t stop it at the border’
Experts in the Government are also working on the issue of protecting the UK’s flora and fauna from invaders.
Native spruce trees are at risk from a European beetle and scientists are urging the public to keep an eye out for signs of disease on trees and report it for study.
The spruce bark beetle, Ips typographus, is becoming a worry with much of the south-east, including Norfolk, Suffolk, London and Kent, now subject to a proactive spruce removal area. Landowners are being encouraged to replace the tree with other species.
Prof Nicola Spence, the UK’s chief plant health officer at the Department for Environment, Food and Rural Affairs (Defra), said stopping the beetle’s arrival is almost impossible.
“I can’t regulate that. I can’t stop it at the border because it’s going to come anyway on wind events,” she told The Telegraph.
“Whilst we’re finding it in the south east, what’s at risk is all the spruce forests in Scotland, Wales, the south west. We are very much managing that in the south east to protect the rest of the UK.
“Pest and pathogens present a great risk for UK biosecurity and our ecosystems. The number and diversity we are exposed to have rapidly increased in recent years as a result of climate change and globalisation.
“In recent years we have seen damaging pests, such as Ips Typographus, which has the potential to cause significant damage to Great Britain’s forestry and timber industries, enter the UK through strong winds and survive due to warmer weather.
“We have robust surveillance and eradication measures in place to tackle outbreaks, but it is crucial we continue to adapt to a changing climate and build the resilience of our trees and plants if they are to survive.”
Meanwhile, this summer veterinarians at Defra were preparing for a deluge of tests for bluetongue, an infection that affects farm animals such as cattle and sheep, and is characterised by a blue tongue in infected animals.
Midges, belonging to the culicoides species, spread the virus to anything they bite, which includes sheep, deer, llamas and goats. It does not affect people or food security, experts say.
Farmers, vets and Government scientists up and down the country have been put on high alert for bluetongue, with the latest Government guidance saying “infected culicoides may be spread to Great Britain via the wind” from the coastal clusters in Germany, the Netherlands and Belgium.
There is a “medium” risk of incursion of a midge that carries a disease for which there is no vaccine, experts say.
Ele Brown, the UK deputy chief veterinary officer, said: “Vector-borne diseases account for more than 17 per cent of all infectious diseases in humans around the world, with mosquitoes and ticks representing a growing threat to the UK due to the fact that they are both established and invasive.
“Climate change, in the form of warmer summer temperatures and milder wetter winters, could increase the abundance of the native mosquito populations, prolong the active vector season and enable invasive mosquito species to establish in the UK and increase their ability to transmit diseases.
“Defra and UKRI are investing more than £7 million in a series of research proposals to improve our capacity and capability to forecast, understand, mitigate and avoid animal and human vector-borne disease threats.”
