Prevention of Lyme borreliosis

People acquire Lyme borreliosis through bites from infected Ixodid ticks, the vector hosts. The infection cannot be passed person-to person, nor from other animals. Peak times for ticks to take blood meals are late spring, early summer and autumn, although there may also be a low level of tick feeding activity in mild winter periods. The main feeding hosts for larval and nymphal ticks are small mammals such as field mice and voles, and birds including blackbirds and pheasants [1]. These hosts may also be reservoirs of B. burgdorferi, and the tick feeding patterns ensure the organism’s continuing cycle between generations of reservoir and vector hosts. Humans are incidental hosts for tick feeds. Fortunately only a minority of ticks carry borreliae, and borrelial transmission usually occurs late in the feed. It is unlikely to occur in the first 18 hours of attachment.

Human infection risk can be minimised by:

• Tick-awareness
• Keep to footpaths and avoid long grass where possible when out walking
• Wearing appropriate clothing in tick-infested areas (long sleeved shirt and long trousers tucked into socks). Light coloured fabrics are useful, as it is easier to see ticks against a light background
• Using insect repellents, e.g. DEET-containing preparations
• Inspecting skin frequently and removing any attached ticks
• Checking again for ticks, especially in skin folds, including armpits, groins, backs of knees and waistband area, at the end of the day

• A shower or bath after returning from a tick-infested area helps to reduce risk

• Making sure that children’s head and neck areas, including scalps, are properly checked
• Checking that unfed ticks are not brought home on clothes
• Checking that pets do not bring unfed ticks into the home on their fur

Methods of tick removal

Remove ticks by gently gripping them as close to the skin as possible, preferably using fine-toothed tweezers or similar implements, and pulling steadily away from the skin [2]. Some veterinary surgeries and pet supply shops sell inexpensive tick removal devices, which are useful for people who are frequently exposed to ticks. Lighted cigarette ends or match heads are not recommended because of the risk of skin damage. Some researchers consider that application of creams or volatile oils to cover a tick and force it to detach may increase risk of borrelial transmission, as it could stimulate the tick to regurgitate potentially infected material.

Antibiotic prophylaxis following a tick bite is not currently routinely recommended.

References

1. Stanek G, Wormser GP, Gray J, Strle F. Lyme borreliosis. Lancet, 2012; 379:461 - 473

2. Centers for Disease Control. Tick Removal. http://www.cdc.gov/lyme/removal/index.html

Last reviewed: 23 March 2012