The threat of a deadly tick-borne virus is on the rise in the UK with parts of Norfolk recording the highest number of detections in the country.

The UK Health and Security Agency (UKHSA) has issued a warning after the first domestic infection of encephalitis was confirmed in Yorkshire.

It comes as recent studies have shown that Thetford Forest has the highest prevalence of the virus in England.

Eastern Daily Press: Thetford Forest has the highest prevalence of the tick-borne disease in the countryThetford Forest has the highest prevalence of the tick-borne disease in the country (Image: Archant)

Tick-borne encephalitis virus (TBEV) is already common in many parts of Europe and is an important cause of viral infections in the central nervous system, according to the World Health Organisation.

It can cause a range of illnesses from completely asymptomatic infection, to mild flu-like illness, to severe infection in the central nervous system such as meningitis or encephalitis.

READ MORE: Met Office warning amid high pollen count in East Anglia

Encephalitis is an uncommon but potentially deadly condition in which the brain becomes swollen.

Public Health England researchers found in 2019 that Thetford Forest had the highest prevalence of the disease in the country and there are fears it is becoming more widespread across the UK.

Eastern Daily Press: Hikers are advised to wear trousers and long-sleeve tops to avoid getting bitten by ticksHikers are advised to wear trousers and long-sleeve tops to avoid getting bitten by ticks (Image: Archant)

Ian Jones, professor of virology at the University of Reading, said wearing appropriate clothes “essentially removes the risk”.

“Tick-borne encephalitis virus was reported in ticks in Thetford Forest in 2019 and today’s update would suggest that it has now become established at other sites and caused sporadic disease in people,” he said.

“Genetically the UK viruses have been close to European or Scandinavian strains so they may have originally arrived from the near continent in ticks attached to birds.

READ MORE: Norfolk's only canal stays closed as dogs leave 'trail of destruction

“The virus is found naturally in some ticks and gets transferred to a person if they are bitten (only if the tick is infected), usually on bare arms and legs whilst walking through undergrowth."

While the danger of infection may be increasing, the risk is still low.

Dr Meera Chand, deputy director at the UK Health Security Agency, added: “Our surveillance suggests that tick-borne encephalitis virus is very uncommon in the UK and that the risk to the general population is very low.”

How ticks feed on blood

Ticks are small, spider-like creatures that feed on the blood of animals, including people, according to the UKHSA.

The size of a tick can vary, with a larva being as small as a tiny freckle, and fully fed females similar in size to a baked bean.

Ticks survive in many habitats but prefer moist areas with leaf litter or long grass, like in woodland, grassland, moorland, heathland and some urban parks and gardens.

Ticks don’t fly or jump. They wait on vegetation for a host to pass by, and then climb on.

They bite and attach to the skin and feed on blood for several days, before dropping off.

Ticks are found throughout the year but are most active between spring and autumn.

How to avoid ticks

  • Walk on clearly defined paths to avoid brushing against vegetation.
  • Wear light-coloured clothes so ticks can be spotted and brushed off.
  • Use repellents such as DEET.
  • Carry out a tick check - Make it a habit to check your clothes and body regularly for ticks when outdoors and again when you get home. Check your children and pets as well. 

What to do if you find a tick

  • Remove ticks as soon as possible.
  • The safest way to remove a tick is to use a pair of fine-tipped tweezers or a tick-removal tool.
  • Grasp the tick as close to the skin as possible.
  • Pull upwards slowly and firmly, as mouthparts left in the skin can cause a local infection.
  • Clean the bite area with antibacterial soap and water, and monitor it for several weeks for any changes.
  • Contact your GP promptly if you begin to feel unwell with flu-like symptoms or develop a spreading circular red rash. Remember to tell them you were bitten by a tick or have recently spent time outdoors.