Lyme disease in children: the tick-bite rash, tests and treatment in the UK

Lyme disease is an infection caused by bacteria carried by some ticks. Ticks are tiny spider-like creatures that live in woods, long grass and sometimes in urban parks and gardens. They do not jump or fly; they attach to the skin of people or animals that brush past, bite in and feed on blood for a few days before dropping off. The NHS says not all ticks in England carry the bacteria, but it is still important to remove them promptly.

Children are often outdoors in the places where ticks live, such as parks, woods, heath and gardens, and a tick bite is not always painful, so it may go unnoticed. NICE says tick bites may not always be noticed. This is why checking children's skin and clothing after outdoor play is a standard part of the advice.

The NHS describes a circular or oval rash around a tick bite as an early symptom of Lyme disease in some people. It can appear up to 3 months after the bite, but usually appears within 1 to 4 weeks, and can last for several weeks. It may have a darker or lighter area in the centre and might gradually spread. On brown and black skin it can be harder to see and may look like a bruise.

Some people also develop flu-like symptoms a few days or weeks after the bite, such as a high temperature, headache, muscle and joint pain and tiredness. If treatment is delayed, more severe problems may appear months or years later, including joint pain and swelling, nerve problems, heart problems and trouble with memory or concentration.

NICE adds that a quick rash after a tick bite that appears and fades within about 48 hours, and is more likely to be hot, itchy or painful, may be a reaction to the bite or a common skin infection rather than erythema migrans. NICE also lists less common features that may prompt doctors to consider Lyme disease, including facial palsy, meningitis, inflammatory arthritis, heart rhythm problems and eye inflammation.

• A slowly expanding red or pink ring or oval, often at the site of a bite but sometimes a bruise-like patch on darker skin.

• Fever, sweats, tiredness, headache, neck pain or stiffness, and migratory aches in muscles or joints.

• Weakness or drooping of one side of the face, severe headache with neck stiffness, a swollen joint or palpitations, which need prompt medical assessment.

The NHS advises removing a tick with fine-tipped tweezers or a tick-removal tool. Grasp the tick as close to the skin as possible, pull upwards slowly without squeezing or crushing it, dispose of it, and clean the bite with antiseptic or soap and water. The chance of getting ill is low and you do not need to do anything else unless a rash or illness appears.

NICE says people should not be diagnosed with Lyme disease if they have no symptoms, even after a tick bite. If your child becomes unwell or develops a rash in the following weeks, tell the GP or NHS 111 about the bite or about any visit to a tick area, including woods and grassy places, in the previous 3 months.

Diagnosis starts with the history and examination. A child with a typical erythema migrans rash is diagnosed and treated on the basis of the rash alone, because blood tests can be negative in early infection. NICE specifically recommends diagnosing and treating without laboratory testing in this situation.

For people without the rash but with symptoms that could fit Lyme disease, NICE recommends combining the clinical picture with laboratory testing. The usual first step is an ELISA blood test, followed by an immunoblot if the ELISA is positive or unclear. If an early ELISA is negative but Lyme disease is still suspected, it may be repeated 4 to 6 weeks later, and an immunoblot is performed for people who have had symptoms for 12 weeks or more. The NHS says the tests are not always accurate in the early stages and that retesting may be needed.

NICE says tests should be done in UKAS-accredited laboratories with validated methods, and cautions against diagnosing on the basis of tests done outside the NHS unless these standards are met. The NHS warns that some websites offer tests and treatment that may not be supported by scientific evidence and advises speaking to a doctor first.

Treatment is a course of antibiotics, started as soon as possible. The NHS says the antibiotic depends on symptoms and that treatment may last up to 28 days, and that the course should be finished even if the child feels better. If symptoms are severe, a hospital specialist may arrange antibiotics directly into a vein.

NICE has separate tables of antibiotic choices for children under 12 and for people aged 12 and over, and the dose is based on weight and the features of the illness, so this is not something to calculate at home. NICE recommends that a paediatrician, paediatric infectious disease specialist or paediatric neurologist, depending on symptoms, is involved in management of children and young people unless there is a single rash and no other symptoms.

Most people get better after antibiotic treatment. The NHS says recovery can take months for some people and symptoms should improve over time.

The NHS says that a few people who have been treated continue to have symptoms such as tiredness, aches and loss of energy, which can last for years. These are often compared to fibromyalgia and chronic fatigue syndrome. It is not clear why this happens to some people, and there is no agreed treatment.

If a child's symptoms come back or do not improve after antibiotics, speak to a doctor. They may offer further support, such as telling the school that a gradual return to activities is needed, or involving children and families' social care to arrange help. NICE makes the same point about school liaison.

The NHS suggests covering skin when walking outdoors and tucking trousers into socks, using insect repellent on clothes and skin (products containing DEET are described as best), staying on clear paths where possible, wearing light-coloured clothing so ticks are easier to see, and brushing ticks off. It also advises regularly checking clothes, skin, and children and pets after being outdoors.

NICE also tells clinicians to advise people on how to check themselves and their children for ticks on the skin, and the NHS says ticks are not always noticed because bites are not always painful. Check the whole body, not just the legs, after time outdoors.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if your child has been bitten by a tick, or has visited an area in the past 3 months where infected ticks could be, and either feels unwell with flu-like symptoms or has a round or oval rash.

NICE lists facial palsy, meningitis and heart problems among the less common features of Lyme disease. None of these is specific to Lyme disease and each can have other causes, so a child with drooping of one side of the face, a stiff neck with severe headache, or a very fast or irregular heartbeat needs urgent medical assessment whatever the reason. Call 999 or go to A&E if you are worried that your child is seriously unwell.