The month of May has not been as hot this year as it was last year (thank goodness!), but that has not kept the tick population at bay. Despite dips, sprays, powders and flea collars, I still pick a few ticks off the dogs each day.
I haven't yet found a tick on the horses this year, but I am sure I will before this month is over. And where there are ticks, there may well be Lyme disease.
The major concern about Lyme disease is, of course, the effect it has on human beings, but this disease can attack any animal. Horses are a prime target for ticks, so it is important for horsemen to know and understand as much about Lyme disease as possible.
Lyme disease first came to public attention in 1975 in picturesque Lyme, Conn., when there was an unusually severe outbreak of this arthritis-like disease. The huge number of people who were affected in the town of Lyme allowed epidemiologists to study the disease closely.
The disease became forever linked with the town through its name, although the disease is no longer strictly a regional problem. In fact, Lyme disease has been reported on five continents and in at least 39 of the 50 states.
Lyme disease had gone unreported, although a similar problem was reported in Europe in 1908 and in 1969 a case was documented in a Wisconsin outdoorsman. There are some 1,500 cases of Lyme disease reported each year, making this the most common tick-transmitted disease in this country.
Lyme disease is spread by a microscopic organism called a spirochete. The spirochete is carried in a tick and transmitted when the tick bites.
There are several types of ticks that harbor the disease-carrying spirochete, but the most common one is the northern deer tick. When the tick bites an animal or a human being, the spirochetes divide and spread throughout the animal's body tissues, causing an inflammatory reaction. Eventually the organism spreads throughout the body and begins causing problems in various organs and body systems.
When a human being is bitten by a Lyme-carrying tick, a noticeable rash develops on the body, helping in the diagnosis. Diagnosis is much more difficult in animals such as horses, however, because animals do not display the tell-tale rash.
A recurrent lameness is the most common sign that a horse is suffering from Lyme disease. Fever, lethargy and lack of appetite are also symptoms of the disease.
Another thing to keep an eye out for is that the affected joints will become hot, swollen and painful. The joints most often affected include the pastern, shoulder, elbow and stifle.
The symptoms of Lyme disease in horses are like those of several other diseases. Therefore, making a diagnosis of Lyme disease is very difficult. The diagnosis is most often made by eliminating all other possible diseases.
The suspicion of Lyme disease will be increased when making the diagnosis if the horse is exposed to a heavy tick infestation or if the horse has traveled to a tick-infested area.
There are some clinical tests available to confirm the presence of antibodies indicating the Lyme disease spirochete, but false-positive results have been prevalent in tests.
If your veterinarian makes a diagnosis of Lyme disease in your horse with some confidence, there are several courses of treatment available. Most treatments are quite successful, especially if they are started early in the course of the disease.
Horses usually show a marked improvement after receiving antibiotics for three or four days. This period of time is not enough to effect a complete cure, however. Treatment must be continued, usually for a period of weeks, to be completely effective.
Prevention is naturally the best method to employ when trying to combat Lyme disease. This means that you must control ticks in your horse's environment. You can use sprays and creams available for this purpose, but you must be sure to use them often enough to be effective.
Routine checks of your horse's body and speedy removal of any ticks you find is the best method to keep Lyme disease at bay.