The prevalence of diseases transmitted by tick bite have increased in recent years, within the UK. And it is now recognised that there are 3 main infections

• Lyme Disease
• Tick-Bourne Encephalitis
• Babesia

Lyme Disease (Borrelia burgdorferi)

• UK Prevalence: In 2019 alone there were >1600 lab confirmed casesin England and Wales, with a further 2000 without lab confirmation.
• Vector: Deer Ticks
• Geography:
  • UK – Most common in southern England and Scottish highlands (but in Yorkshire too)
  • World – More prevalent in parts of central, eastern and northern Europe (including Scandinavia) and parts of Asia, the US and Canada.
• Seasonallity: Summer predominance (but can happen year round)

Clinical Presentation

• Often bite not noticed
• Normal itchy bite rash
• Erythema migrans (click HERE for more images)
• fever and sweats
• swollen glands
• malaise
• fatigue
• neck pain or stiffness
• migratory joint or muscle aches and pain
• cognitive impairment, such as memory problems and difficulty concentrating (sometimes described as ‘brain fog’)
• headache
• paraesthesia.

Treating and testing

• Erythema Migrans – Diagnose and treat Lyme disease without laboratory testing in people with erythema migrans.
• No Erythema Migrans – If there is a clinical suspicion of Lyme disease in people without erythema migrans:
  • Offer an enzyme-linked immunosorbent assay (ELISA) test for Lyme disease
  • Consider starting treatment with antibiotics while waiting for the results if there is a high clinical suspicion.
• Treatment – NICE treatment table
  • First line – Doxycycline 200mg OD 21 day
  • Central Nervous System Or Unstable Carditis – 2g Ceftriaxone IV (see nice for full regime)

Tick-Bourne Encephalitis

• UK Prevalence: Two possible UK cases in 2019 & 2020
• Vector: Deer Ticks
• Geography: 
  • UK – Thetford and New forests Hampshire/Dorset (the south)
  • World – Forrested areas Central/eastern/northern Europe, Siberia, Russian far-East, China, Japan
• Clinical:
  • 7 day incubation
    • 2/3 asymptomatic
  • Biphasic
    • Phase 1: 2-10days non-specific symptoms (fever, fatigue, headache, myalgia, nausea)
    • Asymptomatic Phase: Generally 7 day (1-33day)
    • Phase 2: Typical presentations are meningitis, meningoencephalitis, myelitis, paralysis, or radiculitis
  • Diagnosis – testing through RIPL (Rare and Important Pathogen Laboroatory)

Babesia

• UK Prevalence: One patient July 2019 (uk transition) – historically 10 all imported
• Vector: Cattle & Deer Ticks
• Geography: 
  • UK – North Devon
  • World – Reports in Europe, USA, Japan
• Clinical:
  • no history of a tick bite in this case
  • presented with fever, jaundice, haemolysis, thrombocytopenia
  • diagnosed based on classical morphological features of the Babesia parasite on a blood film. 

Links

• Lyme disease – NICE
• Lyme in UK – BMJ
• Tick-Bourne encephalitis  – UK Gov
• RIPL – rare and important pathogen lab (UK)
• Babesia – Euro
• Babsia global map – Nat. Microbiol.