By Dr. David Gross
Q: My family is going camping with our dog and I hear there is a disease he can get from ticks. What is it and what can I do to protect him?
A: Both humans and pets, mostly dogs, are susceptible to Lyme disease caused by a corkscrew-shaped bacteria transmitted by the bite of ticks. The bacteria, Borrelia burgforderi, was first identified as the cause of an outbreak of rheumatoid arthritis in children in Lyme, Connecticut in 1982. Lyme disease is probably the most common vector-borne disease (diseases transmitted by insect bites) in the United States and is endemic to the Pacific Northwest. The bacteria can be found in a wide variety of wild small mammals and deer in this area and these animals serve as a reservoir for the disease.
Ixodes ticks (blackleg or deer ticks) feed on an infected wild animal then transmit the bacteria to you or your pet. The only way to contract the disease is from a tick bite so it is very important to protect against this danger. A blood test can measure antibodies to the bacteria but not all people or dogs exposed to the bacteria will show signs of the disease and a positive blood test only means the individual was exposed, not that they have the disease.
Signs of Lyme disease are sudden lameness, pain and sometimes swelling in one or more joints. Animals and people can become feverish, lose their appetite, become dehydrated and have swollen lymph nodes. Humans often develop a skin rash at the location of the tick bite but this is rare in dogs. Severe cases can result in kidney failure and death but this is uncommon. The disease usually responds well to treatment with antibiotics.
Ticks embedded in the skin for over 24 hours spread the infection, so removing them as soon as possible is important. Check your family and your dog at least once a day. Check your dog’s toes, behind ears, under both front and rear legs where they connect to the body, around the tail and all over the head. Favorite sites on people are at the junction of clothing and skin, but a thorough examination is important. Run your fingers through your dog’s fur and feel for small bumps. Pull the fur apart to identify any small bumps.
Embedded ticks are usually black or dark brown and can vary in size from a pinhead to a grape. To remove a tick, grasp it as close to the skin as possible with a fine-tipped tweezers (make certain you have these in your first-aid kit). Try to avoid crushing the tick and pull it off the skin with a steady motion. After the tick is out crush it and kill it then dispose in the trash or down a toilet. Clean the skin where the tick was embedded with soap and warm water. Do not use petroleum jelly, a hot match, nail polish or other weird techniques to remove ticks; the best way is with a tweezers, as described.
There are a number of ways to prevent your dog from getting ticks. You should consult your veterinarian about the technique or product she or he finds most effective. There are also Lyme disease vaccines available for prevention of this disease. Consult your veterinarian about how effective these vaccines are in his or her experience in this part of the world.
D. R. Gross graduated from Colorado State University’s veterinary school in 1960 and was in private practice for ten years. He enrolled in graduate school at Ohio State University earning a M.Sc. degree in 1972 and a Ph.D. degree in 1974. He retired in 2006 as Professor and Head of Veterinary Biosciences, at the University of Illinois, Urbana-Champaign. Dr. Gross is a Fellow of the Cardiovascular Section of the American Physiological Society. During his academic career, he published over 90 papers in refereed scientific journals and over 100 abstracts in proceedings of scientific meetings.