Many people have heard of Lyme disease, but I have found that, depending on the region, few people know much about it. So let’s spend a little time learning, because this can be a potentially serious and preventable illness.
As most people are aware, the organism that causes Lyme disease (Borellia burgdorferi) is transmitted by ticks. However, there is often a misunderstanding about the transmission, as it is not caused by all ticks. In North America, only the eastern and western black-legged tick (Ixodes species) carry the organism. These ticks are fairly regional, which is why you see Lyme disease much more commonly in certain parts of the country. The highest risk areas are the Mid-Atlantic and New England states (anything north of Virginia on the eastern seaboard) and the upper midwestern states. However, these ticks can migrate as host populations move, and a recent report showed a several-fold increase in the black-legged tick population in Ohio. Other areas of the country do show sporadic cases (possibly due to movement of pets from endemic states), so no area is considered completely risk-free.
One of the dangers of Lyme disease is that the symptoms are often subtle and can look like so many other illnesses. Many dogs develop subclinical infection, where they have a mild case that can linger and cause problems over a longer period of time. The most common symptoms are lethargy, fever, lymph node enlargement, and joint pain (including lameness) or swelling. In advanced or prolonged cases, arthritic changes may be permanent and kidney failure can happen. Diagnosis is normally through blood tests to screen for other diseases and then specific tests for the Borellia organism. There are several other diseases that can cause similar symptoms, so your vet will likely recommend a “tick panel” to screen for multiple infections at once. Treatment with appropriate antibiotics is possible, though it usually takes at least a month to resolve and may have life-long symptoms.
Thankfully, prevention is possible. Dogs that live in high risk areas or that have lifestyles that expose them to a large number of ticks (such as dogs that hunt, camp or hike) should be vaccinated against Lyme disease. This vaccine is safe and considered effective, so talk to your vet about it. In lower risk regions, the vaccine is not always recommended, but dogs in the endemic areas should be vaccinated even if primarily indoors.
The other method of preventing disease is to keep ticks from attaching at all. Studies have shown that in order to transmit the disease-causing bacteria, ticks must be attached for at least 24-48 hours. Check your dog daily to see if any ticks are present and remove them right away. To check for ticks, push the hair against the direction of growth until you can see skin, and then look all over the body; sometimes using a flea comb will allow you to find smaller ones. Also, use an appropriate tick preventative as recommended by your veterinarian, such as FirstShield. There are other illnesses besides Lyme disease that can be caused by ticks, so you should be proactive in your tick prevention.