Lyme disease

Published by Bupa's Health Information Team, March 2010.

This factsheet is for people who have Lyme disease, or who would like information about it.

Lyme disease is an infectious disease caused by the Borrelia burgdorferi bacterium. It's spread through tick bites. Lyme disease gets its name from a place called Old Lyme in the US where a large number of people developed the characteristic rash in 1974.

About Lyme disease

Lyme disease is a bacterial infection that is spread by tick bites.

You're most at risk of Lyme disease during the late spring, summer and early autumn. This is because the ticks are more active during this time of year. When the weather is good, you're also more likely to spend time outside.

In 2008, over 800 people in the UK developed Lyme disease. However, the disease is more common in Europe, particularly in Germany, Slovenia and Austria. In the US, more than 25,000 people developed the disease in 2008. Most of these people were in the north-eastern, mid-Atlantic and north-central regions. This is because the disease is more common in forests and wooded areas.

Symptoms of Lyme disease

The first symptom of Lyme disease is often a red rash around the tick bite, although some people don't develop this. The rash appears between three and 30 days after you're bitten. It can become quite large over a few days and may reach up to 15cm across. The rash usually has a bright red outline. As it gets bigger, the centre of the rash may clear. You may notice that the rash feels warm but it probably won't be painful.

You may also have flu-like symptoms, including:

• headache
• fever
• aching muscles or joints
• swollen lymph nodes
• tiredness

These symptoms aren't always due to Lyme disease but if you have them, see your doctor, even if you don't remember being bitten.

Complications of Lyme disease

If you get treatment for Lyme disease early, the infection will usually clear up quickly and won't cause any further problems. However, if you have Lyme disease but don't get treatment, the infection may spread to other parts of your body. This can cause:

• Bell's palsy (a condition in which one side of the face becomes paralysed)
• viral meningitis
• severe headaches
• shooting pains
• heart palpitations
• dizziness
• joint pain

With treatment, all of these symptoms should improve.

If the infection is left untreated for several months, six in 10 people may develop acute arthritis. This is a condition that affects your immune system and can cause severe joint pain and swelling. Arthritis usually affects larger joints like the knee.

If Lyme disease is left untreated long-term, one in 20 people may develop problems with their concentration and short-term memory.

Causes of Lyme disease

Lyme disease is caused by the bacterium Borrelia burgdorferi. It's passed on to humans by ticks. Ticks are tiny spider-like creatures, not insects, which attach to the skin and feed on blood. They usually feed on animals such as deer, sheep or horses. If a tick feeds on an animal infected with Borrelia burgdorferi, they also become infected with the bacterium. When the tick feeds again, it passes the bacteria on.

Ticks live on ground level plants, for example long grass, and can be brushed onto your clothing. The ticks climb up your clothing looking for skin to feed on. They usually attach themselves to your legs, groin or abdomen (tummy).

Lyme disease can't be passed from person to person.

Diagnosis of Lyme disease

Your doctor will ask about your symptoms and examine you. He or she may also ask you about your medical history and whether you might have been exposed to ticks.

If your doctor thinks you may have Lyme disease, he or she may do a blood test. However, this is not always necessary. This is because a blood test isn't very accurate and it can take a long time for any antibodies to show up in your blood. Antibodies are proteins produced by the immune system that fight against bacteria and viruses.

If your doctor does a blood test, he or she should send it to an accredited reference laboratory. Some private laboratories offer Lyme disease testing but they may not be a part of the Health Protection Agency's network.

Treatment of Lyme disease

Lyme disease can be treated by a course of antibiotics, usually taken for 14 days.

You can get Lyme disease more than once. If you do keep getting Lyme disease, it's very important to get treatment early to get rid of the bacteria.

Prevention of Lyme disease

There is no vaccination for Lyme disease so it's important to protect yourself. The following tips can help to reduce your risk of getting bitten by a tick.

• If you're in an area with a tick infestation, keep your skin covered as much as possible. Wear shoes instead of sandals or flip flops and tuck your trousers into your socks.
• Keep to footpaths and don't walk through long grass if possible.
• Brush off any clothes and pets before going back inside after a walk. This will help to get rid of any ticks.
• You may want to use an insect repellent on your skin and your clothing.

If you've been in a tick-infested area, it's important to check your skin carefully for any ticks, including your armpits, groin, behind your knees and around your waist. If you do find a tick, make sure you remove it properly.

For answers to frequently asked questions on this topic, see Common questions.

For sources and links to further information, see Resources.