Cases of Lyme disease have “increased rapidly” in the UK and may be three times more common than the current annual estimate, a study of GP records suggests.

The research also reveals that Scotland has the highest incidence rate as well as the largest number of cases in the UK. This has been blamed on Scotland's "wetter climate and popularity as a hiking destination having the highest number of cases".

The bacterial infection is spread to humans via bites from infected ticks, and symptoms can include a circular red rash often described as a bullseye on a dartboard.

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Not everyone develops this rash, however, complicating diagnosis. Flu-like symptoms such as fatigue, fever and muscle ache are also common.

If it is diagnosed quickly - within eight weeks - health guidelines state that most people will respond to antibiotics.

However, many patients who have missed this treatment window say they have gone on to develop a chronic condition characterised by pain and swelling in joints, nerve and heart problems, debilitating fatigue and neurological problems such as trouble concentrating.

This remains controversial, however, with no medical consensus on whether 'chronic Lyme' actually exists.

The latest findings, published in the journal BMJ Open, are based on an analysis of 8.4 million anonymised records belonging to people registered with GP practices in the UK between 2001 and 2012.

A total of 4,083 cases of Lyme disease infection were identified in the records.

Of these, 1,702 (41.7 per cent) were “clinically diagnosed” Lyme disease, 1,913 (46.9%) were “suspected” Lyme disease, and 468 (11.5%) were “possible” Lyme disease.

The annual total number of cases recorded in the primary care database increased from 60 in 2001 to 595 in 2012, giving rise to a UK estimate of 7738 cases in 2012.

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The current official estimate for the UK is around 2,000-3,000 new cases of Lyme disease annually based on laboratory data in England and Wales and centralised reporting in Scotland.

If the numbers continued to increase post-2012 at a similar rate, the researchers predict there would be more than 8,000 new cases UK-wide in 2019.

Study author Dr Victoria Cairns, a retired medical statistician and former psychiatry academic, who has spoken previously of her own battle with Lyme disease, said the result show "there are many more cases than previously, officially estimated".

Dr Cairns, who collaborated on the paper with colleagues from the Institute of Epidemiology in Frankfurt, Germany, added: “I think GPs certainly know about it, the issue is really for the public to know so that they go to the GP to get diagnosed.

“Because that’s really the big problem with Lyme disease - some people don’t get diagnosed quick enough and then they go on to get long-term problems.”

Lyme disease has become the most common tick-borne infection in many parts of Europe and the USA and high rates in nearby countries had prompted fears the current UK estimate was too low.

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Experts say prevention is the best way to ward off the disease, urging people to avoid dense vegetation, tuck their trousers into their socks and use tick repellents.

In June, Scotland's Chief Medical Officer, Catherine Calderwood, wrote to hospitals and GPs urging them to be vigilant amid an increase in cases.