Lyme disease is an illness caused by a spirochete bacteria, Borrelia burgdorferi, which is transmitted to animals and man through the bite of infected ticks.
The disease is reported worldwide and throughout the United States. The states of New York, Massachusetts, Connecticut, Rhode Island and New Jersey account for the majority of cases in the United States. However, cases are reported from all geographic regions of the country. Different ticks are carriers in the different regions. Ixodes dammini (the deer tick) in the Northeast and midwest, Ixodes scapularis (the black-legged tick) in the South, Ixodes pacificus (the western black-legged tick) in the West and Amblyomma americanum (the lone star tick) found in several regions are all considered vectors. The is growing concern that Dermacentor variabilis (the American dog tick) may also be capable of transmitting the disease. Transmission by biting insects (flies, fleas, mosquitos) is speculated but appears to be quite rare.
Not all ticks are infected. Infection rates in tick populations vary by tick species and geographic region from as few as two percent to 90 percent or more.
Ixodes dammini is responsible for most of the cases of Lyme disease in the northeastern United States. These ticks are found in grassy areas (including lawns), and in brushy, shrubby and woodland sites, even on warm winter days. They prefer areas where some moisture is present. The tick has three life stages: larva, nymph and adult. Each stage takes a single blood meal. They feed on a variety of warm blooded animals including man, dogs, cats, horses and cows. The bite is painless so most victims do not know they have been bitten. The nymphal stage appears to be responsible for most Lyme disease cases. Both the larval stage (about the size of a grain of sand) and nymphal stage (about the size of a poppy seed) attach to a variety of small mammals, but prefer the white-footed mouse, the main reservoir of the Lyme disease bacteria. The adult ticks (about the size of a sesame seed) prefer to feed on white-tailed deer. The entire life cycle requires three separate hosts and takes about two years to complete.
Larval and nymphal deer ticks also attach to birds. Indeed, birds may be a primary means by which the ticks (some infected) are spread from one area to another. Some species of birds also function as a reservoir of infection.
In about 50% of the cases a characteristic rash or lesion called erythema migrans is seen. It begins a few days to a few weeks after the bite of an infected tick. The rash generally looks like an expanding red ring. It is often described as looking like a bull's-eye with alternating light and dark rings. However, it can vary from a reddish blotchy appearance to red throughout. And can be confused with poison ivy, spider or insect bite, or ringworm. At about the same time that the rash develops, flu-like symptoms may appear with headache, sore throat, stiff neck, fever, muscle aches, fatigue and general malaise. Some people develop the flu-like illness without getting a rash.
Seek prompt medical attention if any of these symptoms appear, especially after being bitten by a tick or visiting an area where Lyme disease is common. If possible document the presence of the rash by taking a picture because it may disappear before a physician can see it. A picture in this case is worth 10,000 words!
If ignored, the early symptoms may disappear, but more serious problems can develop months to years later. The later symptoms of Lyme disease can be quite severe and chronic. Muscle pain and arthritis, usually of the large joints is common. Neurological symptoms include meningitis, numbness, tingling, and burning sensations in the extremities, Bell's palsy (loss of control of one or both sides of the face), severe pain and fatigue (often extreme and incapacitating) and depression. Heart, eye, respiratory and gastrointestinal problems can develop. Symptoms are often intermittent lasting from a few days to several months and sometimes years. Chronic Lyme disease, because of its diverse symptoms, mimics many other diseases and can be difficult to diagnose.
Lyme disease is treated with antibiotics. Timely treatment increases chances of recovery and may lessen the severity of any later symptoms in both animals and man. The most effective treatment will be recommended by your physician or in the case of your animals by your veterinarian and will depend on the stage of the disease. Treatment for later stages is more difficult often requiring extended and repeated courses of antibiotic therapy. In animals and man treatment failures and relapses are reported.
When out of doors several precautions can minimize your chances of being bitten.
Lyme disease has been described in dogs, cats, horses cows and goats. Symptoms can include fever, lameness and soreness, listlessness, loss of appetite, swollen glands and joints. Heart, kidney, liver, eye and nervous system problems are also described in animals. Laminitis is reported in horses and cows, as are poor fertility, abortions and chronic weight loss. Temperament changes have been reported in dogs and horses. Untreated animals can develop chronic progressive arthritis.
Symptoms can be intermittent and vary in intensity from mild to quite severe and can mimic many other conditions. If you suspect Lyme disease in your animals consult your veterinarian as soon as possible.
Ticks are most commonly found around the head and neck. They can also be found between the toes, on or in the ears, and in the armpit and groin areas. Because the ticks are so small, you must look very carefully. In animals the symptoms of illness may not develop for several weeks or months following tick bite.
If you travel into tick infested areas with your animals, it is possible to bring home on the animals ticks that can infest your premises. If animals in your area develop Lyme disease it should alert you that you are also at risk.
Prompt removal of ticks decreases the chances of getting Lyme disease. The proper and easiest method is to grasp the tick with fine tweezers, as near the skin as you can, and gently pull it straight out. Be careful not to squeeze the tick when removing it which could result in more bacteria being injected. Do not try to remove the tick with your fingers or attempt to remove with lighted cigarettes, matches, nail polish, or vaseline.
Once removed save the tick for identification. Accurate identification becomes very important if you or your animals develop disease symptoms. Proof of tick bite and the kind of tick doing the biting is especially important to document in areas where Lyme disease is not considered prevalent and doctor suspicion is low.
In most areas, ticks can be submitted for identification through local or state health department offices. Many physicians and veterinarians will also submit ticks. Put the tick in a tightly closed container with a small amount of alcohol (rubbing alcohol will do). Mark it with your name, address and phone number, date collected, host collected from (animal or man) and recent travel history.