Ticks and lyme disease
Some people just seem to attract ticks - one Scarborough member removed 18 from his body after a single walk, while another who regularly walks over 1,000 miles a year has never (knowingly) played host to one.
These tiny spider-like creatures attach themselves to plants, waiting for a warm-blooded animal to pass by.
They then crawl to a cosy spot and start sucking blood.
Unfortunately, this is a very efficient way of spreading infections from previous victims, which might have included sheep, deer or small rodents.
In some areas, up to 30% of ticks can be infected with, lyme disease a bacterial infection, which in extreme circumstances, can kill or paralyse.
Ticks are tiny arachnids, related to spiders, found in woodland and heath areas that feed on the blood of mammals.
If a larval tick picks up an infection from a small animal such as a vole, when it feeds as a nymph it can pass the infection to the next animal or human it bites.
Ticks cannot jump or fly, but when they are ready for a meal, they will climb a nearby piece of vegetation and wait for a passing animal to catch their hooked front legs. The tick will not necessarily bite immediately, but will often spend some time finding a suitable site on the skin.
Once a tick has started to feed, its body will become filled with blood.
Adult females can swell to many times their original size. As their blood sacs fill they generally become lighter in colour and can reach the size of a small pea, generally grey in colour. Larvae, nymphs and adult males do not swell as much as they feed, so the size of the tick is not a reliable guide to the risk of infection. If undisturbed, a tick will feed for around 5 to 7 days before letting go and dropping off.
The bite is usually painless and most people will know they have been bitten only if they happen to see a feeding tick attached to them.
The risk of infection increases the longer the tick is attached, but can happen at any time during feeding. A Public Health England leaflet for GPs points out that disease transmission can be in less than a day. As tick bites are often unnoticed, it may be difficult to determine how long it has been attached. Any tick bite should be considered as posing a risk of infection.
Adults are most often bitten around the legs. Small children are generally bitten above the waist—check their hairline and scalp.
Lyme disease can affect your skin, joints, heart and nervous system.
What are the symptoms of lyme disease?
The earliest and most common symptom of lyme disease is a pink or red circular rash that develops around the area of the bite, three to 30 days after someone is bitten. The rash is often described as looking like a bull’s-eye on a dart board.
You may also experience flu-like symptoms, such as tiredness, headaches and muscle or joint pain.
If lyme disease is left untreated, further symptoms may develop months or even years later and can include muscle pain, joint pain and swelling of the joints, and neurological symptoms, such as temporary paralysis of the facial muscles
Lyme disease in its late stages can trigger symptoms similar to those of fibromyalgia or chronic fatigue syndrome. This is known as chronic lyme disease, although more research into this form is needed.
A person with lyme disease is not contagious because the infection can be spread only by ticks.
Unless in its early stages when a rash is present, diagnosing lyme disease is often difficult as many of the symptoms are similiar to those of other conditions.
If lyme disease is suspected, blood tests may be able to confirm the diagnosis, but they often need to be carried out a few weeks after infection to reduce the risk of false-negative results.
Diagnosed cases of lyme disease can be treated with antibiotics. Your course of antibiotics will depend on the stage of your lyme disease, but you will usually need to take them for two to four weeks.
How common is lyme disease?
Lyme disease is the most common tick-borne infectious disease in Europe and North America. People who spend time in woodland or heath areas are more at risk of developing lyme disease because these areas are where tick-carrying animals, such as deer and mice, live.
Public Health England estimates there are 2,000 to 3,000 cases of lyme disease in England and Wales each year, and that about 15%-20% of cases occur while people are abroad.
Parts of the UK known to have a high population of ticks include the North York Moors.
Most tick bites happen in late spring, early summer and autumn because these are the times of year when most people take part in outdoor activities.
Preventing lyme disease
There is currently no vaccine to prevent lyme disease. In 2002, a vaccine was introduced in the United States but it was withdrawn because of concerns over side-effects.
The best way of preventing lyme disease is to avoid being bitten when you are in wooded or heath areas known to have a high tick population. The following precautions might help prevent lyme disease:
Removing a tick
If you do find a tick on skin, remove it by gently gripping it as close to the skin as possible, preferably using fine-toothed tweezers, and pull steadily away from the skin.
Contrary to myth, the tick's "head" is not attached to the victim - there is only a fine, barbed tube, which can remain in place if the tick is not carefully removed.
A twisting action is not more effective with standard tweezers, although some popular tools, such as the O'Tom Tick Tweezer, are designed to be employed in this way.
Never use a lit cigarette end, a match head or essential oils to force the tick out. Coating with vaseline is occasionally suggested, but although this can eventually suffocate the tick, it will take from four to 48 hours to work.
*The text of this article includes an edited versions of pages, and illustrations, from various authoritative sources, primarily NHS Choices and Lyme Disease Action..