Lyme disease

Lyme disease is a bacterial infection that infected ticks pass on to humans. You may also hear it called Lyme borreliosis.

Ticks are tiny, spider-like creatures. They live in woodland and moorland areas, in grassy places, and in parks and gardens, and they feed on the blood of birds and mammals, humans included.

The earlier Lyme disease is diagnosed, the easier it usually is to treat.

Many people with early Lyme disease develop a circular rash around the tick bite. The rash:

• usually develops around 3 to 30 days after you have been bitten
• may look like a bull's-eye on a dart board
• will be red
• may feel slightly raised at the edges
• may get bigger over several days or weeks
• is usually around 15 cm (6 inches) across, but it can be smaller or much larger

Some people develop several rashes in different parts of the body.

Around 1 in 3 people with Lyme disease will not develop a rash.

Some people have flu-like symptoms in the early stages of Lyme disease. These can include:

• tiredness (fatigue)
• muscle pain
• joint pain
• headaches
• a high temperature (fever)
• chills
• neck stiffness

Speak to a doctor if you've been bitten by a tick and you:

• develop a rash
• have flu-like symptoms

Remember to tell the doctor you've been bitten by a tick.

Lyme disease is often hard to diagnose, because many of its symptoms look like those of other conditions.

Doctors use 2 kinds of blood tests to diagnose Lyme disease. But the tests are not always accurate in the early stages, so a result can be wrong. If you still have symptoms after a negative result, you may need to be tested more than once.

If you have symptoms of Lyme disease, you'll usually be given antibiotics. Finish the whole course even if you start feeling better, because this helps make sure all the bacteria are killed.

If your symptoms are particularly severe, you may need antibiotic injections (intravenous antibiotics).

Some of the antibiotics used for Lyme disease can make your skin more sensitive to sunlight. So avoid spending long periods in the sun, and don't use sunbeds until you have finished the treatment.

In some cases, symptoms carry on after the antibiotics are finished. This is called post-treatment Lyme disease syndrome. There's currently no agreement on the best treatment for it, because the underlying cause is not yet clear.

Be wary of internet sites offering alternative diagnostic tests and treatments for Lyme disease. These may not be supported by scientific evidence.

Some animals carry the bacteria that cause Lyme disease. When a tick bites one of these animals, the tick becomes infected, and it can then pass the bacteria on to a person by biting them.

Ticks don't jump or fly. They climb on to your clothes or skin if you brush against something they're sitting on. Then they bite into the skin and start feeding on your blood.

The longer a tick stays attached to your skin, the more likely you are to become infected with Lyme disease. So it matters to remove ticks quickly. But ticks are very small and their bites don't hurt, so you may not realise one is attached to you.

Your risk of getting Lyme disease is higher in some situations:

• if you spend time in woodland or moorland areas
• from March to October, because more people are outdoors then

Only a small number of ticks carry the bacteria that cause Lyme disease, so being bitten doesn't mean you'll definitely be infected. Still, you should know the risk exists. If you start to feel unwell, see a doctor.

There's no vaccine for Lyme disease at the moment, but you can take some steps to help prevent tick bites.

• stay on paths and avoid long grass when you walk outdoors
• wear a long-sleeved shirt and trousers tucked into your socks when you walk outdoors
• wear light-coloured clothes for walking, as this may help you spot a tick on them
• use insect repellent on exposed skin
• check your skin and clothing for ticks after you've been outdoors
• check your children's skin for ticks, especially around the head and neck, including the scalp
• check that pets don't bring ticks into your home in their fur

If Lyme disease isn't treated, or isn't treated early, more serious symptoms can develop. These can include:

• pain and swelling in the joints
• nerve problems, like numbness or pain in your limbs
• memory problems
• difficulty concentrating
• heart problems

Some of these problems will get better with treatment, but they can continue if treatment starts late.

Some people develop long-term symptoms after Lyme disease. These may be like the symptoms of fibromyalgia or chronic fatigue syndrome. This is known as post-treatment Lyme disease syndrome.

It's not clear why this happens, but it may be linked to overactivity of your immune system.