Lyme disease: chronic illness is rare, say expertsBMJ 2019; 367 doi: https://doi.org/10.1136/bmj.l5975 (Published 10 October 2019) Cite this as: BMJ 2019;367:l5975
People who have had Lyme disease rarely develop chronic problems, experts have said, warning that those who seek treatment abroad believing their symptoms are a result of the infection may be putting themselves at risk.
There are around 1000 laboratory confirmed cases of Lyme disease in England and Wales annually, with an estimated 2000 more cases successfully treated in primary care without positive blood tests, said experts at a briefing on the disease at the Science Media Centre on 9 October.
Of these patients, fewer than one in 20 experience residual symptoms. Those that have confirmed neurological Lyme disease—a late complication present in about one in 10 cases—have a higher rate of long term subjective symptoms, such as fatigue and poor concentration.
But according to Matthew Dryden, consultant microbiologist for Hampshire Hospitals NHS Trust and who has seen many cases of Lyme disease, “In most cases, patients with true Lyme do not develop chronic symptoms.”
Lyme disease is contracted from infected ticks, which are often spread by small rodents and deer.
Dryden and others at the briefing warned that an increase in public awareness of the disease has led to misinformation, particularly around “chronic” or “‘post-treatment” Lyme disease.
They stressed that patients presenting with multisystem symptoms, that are often comparable to chronic fatigue, should be wary of seeking non-validated tests, many of which involve samples being sent abroad.
Sarah Logan, a consultant in the tropical diseases unit at University College London Hospital, said that long term antibiotics for patients who believe they have chronic Lyme disease can be more harmful than the disease itself.
She recounted the case of a patient who contracted an infection from a long term intravenous line that had been fitted abroad to provide them with antibiotics. Other patients have contracted Clostridium difficile and drug resistant infections from long term antibiotic therapy, she said.
The increase in cases may be because of better awareness and wider testing as well as an actual increase in cases, the briefing heard. Lyme disease is present in 1.9% of ticks in the UK. Their presence in more parts of the UK may be attributed to climate change and changes in land use, although more research is needed.
Asked whether people should avoid outdoor pursuits in places where Lyme disease is present in the tick population, Tim Brooks, clinical services director at Public Health England’s rare and imported pathogens laboratory, said, “You’re just as likely to contract Lyme disease in your back garden as you are in the countryside.” Awareness campaigns should not stop people from enjoying outdoor activities, he said.
A recent innovation in Scotland, where Lyme disease is present in the Highlands, is an app that uses satellite and GP data to map the presence of ticks.1