Lyme disease is a bacterial infection spread to humans by infected ticks. It's also known as Lyme borreliosis.
Ticks are tiny spider-like creatures found in woodland and moorland areas. They feed on the blood of birds and mammals, including humans.
Lyme disease is usually easier to treat the earlier it's diagnosed.
Find out more about tick bites and how to treat them
Symptoms of Lyme disease
Many people with early symptoms of Lyme disease develop a circular rash around the tick bite. The rash:
- usually develops around 3 to 30 days after you've been bitten
- is often described as looking like a bull's-eye on a dart board
- will be red and the edges may feel slightly raised
- may get bigger over several days or weeks
- is typically around 15 cm (6 inches) across, but it can be much larger or smaller
Some people may develop several rashes in different parts of their body.
Around 1 in 3 people with Lyme disease won't develop a rash.
Other symptoms of Lyme disease
Some people with Lyme disease also have flu-like symptoms in the early stages, like:
- tiredness (fatigue)
- muscle pain
- joint pain
- a high temperature (fever)
- neck stiffness
Later symptoms of Lyme disease
More serious symptoms may develop if Lyme disease is left untreated or is not treated early. These can include:
- pain and swelling in the joints
- nerve problems – such as numbness or pain in your limbs
- memory problems
- difficulty concentrating
- heart problems
Some of these problems will get better slowly with treatment. But they can persist if treatment is started late.
A few people with Lyme disease go on to develop long-term symptoms similar to those of fibromyalgia or chronic fatigue syndrome. This is known as post-infectious Lyme disease. It's not clear exactly why this happens. It's likely to be related to overactivity of your immune system rather than continued infection.
How you get Lyme disease
If a tick bites an animal carrying the bacteria that cause Lyme disease, the tick can become infected. The tick can then transfer the bacteria to a human by biting them.
Ticks don't jump or fly. They climb on to your clothes or skin if you brush against something they're on. They then bite into the skin and start to feed on your blood.
Generally, you're more likely to become infected if the tick is attached to your skin for more than 24 hours. Ticks are very small and their bites are not painful, so you may not realise you have one attached to your skin.
Where are ticks found?
Ticks are found throughout the UK and in other parts of Europe and North America. There are a high number of ticks in the Scottish Highlands.
They can be found in any areas with deep or overgrown plants where they have access to animals to feed on.
They're common in woodland and moorland areas, but can also be found in gardens or parks.
Who's at risk of Lyme disease?
The risk of getting Lyme disease is higher:
- for people who spend time in woodland or moorland areas
- from March to October because more people take part in outdoor activities
It's thought only a small proportion of ticks carry the bacteria that cause Lyme disease. Being bitten doesn't mean you'll definitely be infected. However, it's important to be aware of the risk and speak to a GP if you start to feel unwell.
Diagnosing Lyme disease
Diagnosing Lyme disease is often difficult as many of the symptoms are similar to other conditions.
There are 2 kinds of blood test use to diagnose Lyme disease. The tests are not always accurate in the early stages of Lyme disease. So you may need tested more than once if you still have symptoms after a negative result.
Treating Lyme disease
If you have symptoms of Lyme disease, you'll normally be given antibiotics.
If you're prescribed antibiotics, it's important you finish the course even if you're feeling better. This'll help ensure all the bacteria are killed.
If your symptoms are particularly severe, you may need antibiotic injections (intravenous antibiotics).
Some of the antibiotics used to treat Lyme disease can make your skin more sensitive to sunlight. You should avoid prolonged exposure to the sun and not use sunbeds until after you have finished the treatment.
There's currently no agreement on the best treatment for post-infectious Lyme disease. This is because the underlying cause is not yet clear. Be wary of internet sites offering alternative diagnostic tests and treatments. These may not be supported by scientific evidence.