HEALTH: Watch out for ticks!
The arrival of spring means many of us will begin once again to venture out into the countryside more often.
However, a local wildlife ecologist is warning of the dangers ticks pose to both people and their pets. Not only is an embedded tick itself unpleasant, it may transmit the bacterial condition of Lyme disease.
Ticks are blood sucking insects, closely related to mites. There are approximately 20 British species, but the most common and the one most likely to be encountered by people is the Sheep Tick. This is also known as the Castor Bean Tick because of its rounded shape when it is engorged. These ticks parasitize a range of wild animals, including small mammals and deer. Starting as minute larvae, they develop into first nymphs, then mature adults. They require a blood meal prior to moulting into each subsequent stage. Larvae and nymphs typically feed on small mammals while adult ticks choose larger mammals such as deer.
When seeking a new host ticks perform a distinct behaviour known as ‘questing’. They climb hanging branches, the end of bracken fronds, or the tips of long grass. Here they take on a distinct outstretched posture with their legs outstretched, waiting for animals to walk past. The legs contain sensory organs which detect carbon dioxide and heat. When a potential host is sensed, they quickly fall or move onto it. They then find a suitable location to extract blood. In humans this is often the groin area and in children the head or shoulders. They then bury their mouthparts into to the skin, attaching firmly. They pump saliva containing painkillers in, so nothing is felt when they begin to remove blood.
Ticks are much more widely distributed than previously thought. A study published by researchers at the University of Bristol asked veterinary surgeons to examine dogs brought into them for ticks. Ticks were found on dogs from throughout Derbyshire, South Yorkshire and Nottinghamshire. They have also been reported from around the Chesterfield and the Matlock areas. Deer have become much more abundant in recent years and this has helped spread ticks around.
An embedded tick can cause irritation and redness, but is rarely a problem. They are mostly merely annoying and unpleasant. However ticks do have the potential to spread disease, notably Lyme disease. This is a bacterial infection. Those who become infected often develop a distinctive circular skin rash and develop symptoms typical of a cold. In many cases these clear up with no further problems. However, on occasion if unspotted and untreated further problems can develop in later months, including muscle pain, fatigue, and arthritis amongst others. The number of confirmed cases in the U.K. is increasing, with over 1,000 diagnosed in 2017. If spotted Lyme disease can be easily treated with antibiotics which prevent further complications developing.
Local biologist Mark Walker has specialised on the study of parasitic disease, and spent time in Italy studying Lyme disease in a ‘hotspot’ for the disease. His advice is to:
Avoid areas of dense vegetation such as bracken thickets. This is where ticks are most abundant.
If walking in such areas wear long trousers and a hat. Children are especially likely to be bitten on the head and shoulders and should also wear a hat.
After returning from a walk in woodland or moorland check thoroughly for ticks on the legs and groin area. Embedded ticks can be felt as large raised bumps on the skin. Unembedded adult ticks look like mites; they have four leg pairs and crawl. Ticks should be removed as soon as possible using tweezers; grasping the tick around the mouthparts and twisting free.
Although a tick bite itself does not require medical attention, anyone developing a circular rash often centred on where the tick bite occurred should seek advice. The rash can vary but is often intensely red, with a clear central portion.
Dogs should likewise also be examined for ticks. These can be difficult to spot under the fur. If felt they should be removed using tweezers or special tick removers which can be bought from pet suppliers.