HIGH summer and early autumn are not associated only with Pimm’s on the lawn, but also with the ticks that spread Lyme disease in wooded or scrubby countryside.

The disease was named in 1975 after it was first identified in a number of patients from Lyme, Connecticut. But once doctors and patients had been alerted to it, other cases were soon diagnosed elsewhere. Although the disease is mostly found in the northeastern states of the USA, it is relatively common in California and Oregon and is now well established in the UK, the rest of Europe and even the Far East.

With the change in agriculture and a greater emphasis on the preservation and conservation of a natural environment rather than cultivated fields, it is likely that Lyme disease will become a greater hazard to country people and ramblers. This is because changes in the countryside have already resulted in a notable increase in the deer population; this is likely to increase further as the amount of scrubland and woods multiplies.

Although deer are the favoured host for the tick that carries Lyme disease, other wild animals may act as its vector. Dogs, too, may be the unwitting carrier of what can be a difficult disease to diagnose.

Lyme disease ticks are so small that they often pass unnoticed and will continue to gorge themselves on blood for days. But it takes just 48 hours of latching on to bare human flesh, usually the legs, for the tick to transmit the organism (a spirochete) to the person.

The first sign of trouble is usually apparent within five weeks of picking up the tick — it will be a large red spot, which may be raised. The spot is often found on the patient’s thighs, buttocks or upper arm. The initial spot expands, leaving a clear zone at its centre, but the diameter of the lesion may be as much as 12 inches. Further spots begin to appear in different parts of the body and other symptoms include headache, a raised temperature, aches and pains and sometimes enlarged glands and spleen.

To the patient, it feels as if they have flu — and, just as with a dose of flu, they may suffer residual tiredness and feelings of being slightly under the weather for months. Worse symptoms often follow the initial rash and general malaise. Weeks or months after the tick has been removed or fallen off because it is engorged, six out of 10 patients develop arthritis so acute that it is easily mistaken for rheumatoid arthritis.

Nearly one in 10 people who have had the tick will show signs of damage to their heart muscle and one in six has neurological symptoms, one of the most common of these is Bell’s (facial) palsy. Patients may suffer more than one of the complications.

The best treatment for Lyme disease is to avoid catching it. When walking through scrubland, you are well advised to wear long trousers and socks with hard shoes, and to roll your sleeves down. If a small tick is noticed, it should be removed immediately; grip the tick between the finger and thumb as close to the skin as possible. The tick is first pushed inwards, given a twist and pulled out.

If this can be done within the first 12 hours or so, it is likely that the patient will have escaped infection. Once the rash has appeared, heavy and prolonged courses of antibiotics are needed. Likewise, if the diagnosis is made only after complications have occurred as the rash initially passed unnoticed, the patient may still be cured by antibiotic therapy. Unfortunately, the symptoms linger even after all the spirochetes have been killed by the use of appropriate antibiotic therapy.

Because of the persistence of the symptoms, and the acute pain that is experienced, for example with the arthritic joints, painkillers are also indicated. The arthritic pains may recur from time to time for years. Sometimes the neurological damage is also permanent.

E-mail Dr Thomas Stuttaford your questions on diets