Lyme disease is a condition that was first described in people in Lyme, Connecticut, USA in the 1970s and discovered in dogs in the 1980s. It is an example of a tick-borne disease (see below) and is one of many diseases that are passed between animals using intermediate hosts or vectors.
How is the disease caught?
The disease is transmitted by ticks which, when they bite a dog or human, pass on a microscopic organism called Borrelia burgdorferi. This microscopic bacteria (known as a spirochaete) causes symptoms of the disease once it gets established in the new host. Not surprisingly, the disease is commoner in places where there are many ticks, eg woods where there are deer and rodents who serve as hosts to the ticks. It is rare in urban pets.
What symptoms are shown?
In dogs the main symptoms are stiffness/lameness, painful joints, poor appetite, high temperature and enlarged lymph glands. In people, an early sign of the condition is a skin rash.
How is the diagnosis made?
The symptoms are rather vague and could be caused by many different diseases, but Lyme diseaseis suspected in a dog showing joint pain and fever and which has had possible exposure to ticks. If exposed, dogs make antibodies to the organism, so checking for these can help with diagnosis. Many dogs do however have antibodies without showing signs of illness so a positive result does not conclusively prove the condition. Based on clinical findings and antibody result, treatment may be given. If the dog makes a rapid improvement, Lyme disease will likely have been the cause.
What is the treatment?
Simple antibiotics usually produce a rapid cure. Painkillers may also be given to help with discomfort. The dog should be rested while on treatment and tempted to eat. Treatment usually lasts several weeks to ensure all the bacteria are killed.
Prevention is possible by:
Avoiding areas where ticks are common (not always feasible or known).
Manually removing ticks as soon as they are seen or getting your veterinary surgeon to do so.
Using proprietary tick prevention treatments on dogs, under veterinary advice.
A vaccine is available (in the USA).
Can people catch the infection from infected dogs?
No, infection is only passed on by the vector, so people get infected by being bitten by ticks transmitting Borrelia burgdorferi.
How do you remove a tick from a dog? Two methods are:
Grasp the tick with tweezers very close to its attachment with the skin. Pull back gently and continuously (no need to twist). Alternatively, use a tick removal tool, available from vets or pet shops, which makes removal even easier.
Apply a parasitic preparation, eg Frontline or other accaricidal product, available from vets. This should kill the tick and cause it to drop off within 24 hours. The product can also be used as a prevention measure before any possible exposure to ticks.
Note that it is unusual for head parts to remain within the dog’s skin, but very often an inflammatory nodule forms after tick removal. This is an allergic reaction to the tick’s saliva and not necessarily a sign that head parts have become detached and remain in the dog. The nodule disappears after 1-2 weeks.