Ticks
Tick prevention and removal
Reference BMJ 9/12/2013 Due C. et al!
Prevention and rapid removal of ticks significantly reduces the risk of the transmission of
infections that they may carry – the most well known being Lyme disease.
Ticks are members of the arachnid family, some with hard shells and some with soft.
Those with hard shells are most likely to cause disease ( their mouth is at the front rather
than underneath as in soft ticks).
They have a three stage life cycle:
Larva – 0.5mm with six legs
Nymph 1.5mm long
Adult 3mm long but fed (as in the photo) can be 11mm in length when engorged
Each stage needs a blood feed – usually in spring, summer or autumn.
Soft ticks feed for a few hours, hard ticks for days. They then detach and moult to the next
stage in the cycle. The photo above shows a blood engorged and non-engorged tick.
Lyme disease is the most well known disease, but around the world different continents
have different tick spread disease. Within the UK there are a wide variety of different ticks
with different animal hosts ( see www.bada-uk.org )
TICK PREVENTION AND REMOVAL SUMMARY “1
How to prevent:
1) Education about – like this!
2) Repellants:
1) Lemon Eucalyptus oil (PMD). Studies suggest 100% protection after 5 minutes
2) DEET. Laboratory studies showed 30% (strong) DEET gave repellency of
dropping to 85-91% after 48 hours (animal studies). Has the advantage it can be
applied as often as needed as toxicity has not been demonstrated. AVOID IN
CHILDREN less than 3 years
80-100% but rapidly reduced over 2 -5 hours. Therefore need to remember it
wears off. Public concern about skin applied (topical) effects of DEET largely
have no evidence base, but potentially can be toxic if swallowed. Possible
implication of causing fits in children under 8, but no hard evidence. No bad
effect if applied in pregnancy. Read the label regarding how often to apply.
3) Clothing – Simple measure is to wear protective clothing but not guaranteed to work.
Boots, long trousers tucked in to socks, long sleeved shirts tucked in. Clothes should
be checked every 2 hours during trip and up to a week after – as they hide.
4) Impregnated clothing – Topically applied is unlikely to give 100 % cover as some skin
will be unprotected. So, clothes impregnated with permethrin can help. This is also
used on tents, sleeping bags. Low toxicity and some repellency. More effective than
applying DEET to clothing ( 100% for permethrin vs 86-92% for DEET). Clothing can
be sprayed and reapplied every 20 washes. Clothes can be bought with the chemical
already built in.
5) When outdoors check body every 2-3 hours and thoroughly once returned especially if
visiting a known affected areas.
Removal:
To feed they bite and the part that goes through the skin is anchored by barbs. Some
species also produce cement for double protection (this can cause allergies).
The bacteria that causes Lyme disease lies in the midgut of the tick and after biting moves
up the gut into the tick salivary gland and then the host (human, dog etc). This takes some
time and risk of infection is low if removed 24-36 hours after bite.
The longer attached the higher the risk
Remember most tick bites will not lead to Lyme disease.
TICK PREVENTION AND REMOVAL SUMMARY “2
How to remove
1) Do not use chemicals, vaseline, lit matches, nil polish etc – these do not work and can
cause the tick to burst spreading infectious fluids.
2) Fine pointed tweezers – the NHS and Public Health England recommend this as the
only proven means of removal. Fine tipped forceps grasp the tick as close as possible
to the skin and pull steadily upwards. Do not twist or jerk.
3) Tick removal tools are available but the evidence is based on removing from animals.
The authors of this paper recommended forceps over tools as more studies are needed
to prove safe efficiency.
What to do if bitten:
If bitten by a tick you should keep an eye out for symptoms of Lyme disease. Though
the risk of getting it is very low!
60 % of patients will develop a bull’s eye skin rash over a few days (as opposed to an
allergic reaction which is over a few hours and settles after a day or so). The rash is called
erythema migrans:
Other symptoms may be a flu like illness, headache, facial palsy ( one see of face droops),
joint pain, palpitations.
You should see your GP if you get any, say you were bitten by a tick and then what
symptoms followed.
When I was trained (over 25 years ago now) we were taught that the worst areas for Lyme
disease were usually the New Forrest, Scottish Highlands.
Most cases do arise in the South of the country (76% in 2011), but ticks can be found
anywhere in the UK. Usually where woodland meets scrub, but also in gardens, parks.
TICK PREVENTION AND REMOVAL SUMMARY “3
Resources for healthcare professionals:
Public Health England (www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/LymeDisease/
GeneralInformation/ lym005GeneralInformation/)—Clear information on Lyme disease and links
to other useful websites
Public Health England (www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/LymeDisease/)—
Information on Lyme disease, epidemiological data, and Lyme disease diagnostic services in the
UK. Patient leaflets and recommendations for diagnosis and treatment across Europe and North
America also available
Public Health England (www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/Ticks/
TickPreventionAndRemoval/)—Advice on how to prevent tick bites and minimise ticks in gardens
US Centers for Disease Control and Prevention (www.cdc.gov/ticks/removing_a_tick.html)—
Instructions on tick removal, with a diagram
Resources for patients
Borreliosis and Associated Diseases Awareness UK (www.bada-uk.org/)—Clear information on
many tickborne diseases found in Europe. All of the information is gathered from scientific
resources or research
Patient.co.uk (www.patient.co.uk/health/lyme-disease)—Information on Lyme disease and links to
patient support groups and recent articles