Re: Tick bite prevention and tick removal
We were interested to read the article ‘Tick bite prevention and tick removal’ in the 9th December 2013 issue of the BMJ.1 The article addresses the important subject of prevention of Lyme borreliosis (LB). LB is an increasingly common disease in the UK and can lead to multi-system disease that is difficult to diagnose and manage.2 Hence the importance of preventing infection by education, tick repellants, appropriate clothing and the timely removal of the tick.1
The article states in its summary points (advice to patients) that ‘If bitten in a Lyme disease endemic area, consult your GP to discuss antibiotic prophylaxis’. A meta-analysis investigating the use of antibiotic prophylaxis recommends that prophylaxis is practiced in endemic areas of LB after an Ixodes tick bite.3 However these data suggest that only one case of LB is prevented if 50 patients are treated with prophylactic antibiotics.3 Accurate data on incidence and prevalence are not available for most of the UK and so it is uncertain what areas may be considered endemic for LB. At the present time in the UK we believe the general use of prophylactic antibiotics is not indicated and will increase the workload of GPs and subsequently the cost to the NHS, as well as prescribing unnecessary antibiotics for patients. This view is also in line with the advice presented in the BMJ in May 2012 “ Asymptomatic individuals with tick bite should not be tested for Lyme borreliosis (false positives occur because of past resolved infection and cross reactive antibodies), nor should they receive prophylactic treatment”.4
In Scotland the incidence of LB is currently determined by the reporting of new seropositive cases to Health Protection Scotland from the National Lyme borreliosis testing laboratory, Inverness. These data have shown an increase in the average number of cases of LB over a ten year period from 55 in 2002 to 308 in 2011. However, these figures are from laboratory based data and do not include clinically diagnosed cases seen by clinicians that have not been tested by the laboratory.
The greatest number of cases has been observed in the Highlands region of Scotland for the same time period: 33 in 2002 to 145 in 2011. Anecdotally, GPs in the Highlands have stated that less than 20% of cases are being referred for testing. If this is indeed the case, the incidence of LB is seriously under-reported and there may be some support for the use of antibiotic prophylaxis in Highland at least. The immediate need is for accurate, real time data that will let a reasonable decision be made on the use of antibiotic prophylaxis.
Recently a multi-disciplinary (medical, veterinary, medical geography, epidemiology) group of collaborators have been brought together in Inverness and they intend to address this lack of accurate knowledge using retrospective and prospective data to design real-time maps of LB in Scotland. It is hoped that this will provide both clinicians and patients with up-to-date, accurate information which would help with both the prevention of borrelia infection and lead to the early, effective treatment of LB.
R Evans, S Mavin, S Holden, A Munro, G Gunn
1. Due C, Fox W, Medlock JM, Pietzsch M, Logan JG. Tick Bite prevention and tick removal. BMJ 2013: 347; f7123.
2. British Infection Association. The epidemiology, prevention, investigation and treatment of Lyme borreliosis in United Kingdom patients: a position statement by the British Infection Association. J Infect 2011;62:329-38.
3. Warshafsky S, Lee DH, Francois LK, Nowakowski J, Nadelman RB, Wormser GP. Efficacy of antibiotic prophylaxis for the prevention of Lyme disease: an updated systematic review and meta-analysis. J Antimicrob Chemotherap 2010: 65; 1137-1144.
4. Duncan CJA, Carle G, Seaton RA. Tick bite and early Lyme borreliosis. BMJ 2012: 344;e3124.
Competing interests: No competing interests