Lyme disease most often occurs in the New England states; however, cases have been reported in every state. There are many case reports in the upper Midwest and Pacific coasts. Texas is now also seeing more and more cases of Lyme disease. Recent studies show that this increase is due to Lyme-infected ticks migrating from Mexico.
Lyme disease is caused by the bacteria Borrelia burgdoerferi. The most common ticks to carry this bacteria are Ixodes ticks. These are known as deer ticks or black-legged ticks. These ticks prefer mice or deer to feed on but are willing to feed on people and dogs. Any stage of development can carry the bacteria and spread the disease. Once the tick attaches to its host, it takes one to two days to transmit the bacteria. Spring and fall are the most common times for ticks to feed on hosts and therefore the most likely times for transmission of the disease.
In dogs, the most common symptoms of Lyme disease include fever, inappetence, lameness (particularly shifting leg lameness), swollen lymph nodes, swollen joints and decreased energy. When left untreated, the disease can affect other organs such as the kidneys, brain and heart.
Diagnosis is based on symptoms and history of tick exposure. There are blood tests available to check for antibodies against the bacteria. These antibodies are detectable four to six weeks after the initial infection. Ruling out other tickborne diseases with blood testing is also important. Ehrlichia, Anaplasmosis and Rocky Mountain spotted fever are more common tick-borne diseases seen in Texas and can have very similar symptoms to Lyme disease. There is a comprehensive blood panel available from North Carolina State University that can be very useful when vector-borne diseases are suspected.
Prevention is key with Lyme disease. There are vaccines available, and they may be recommended by your veterinarian based on your pet’s risk of exposure. These vaccines are not 100% effective. The most important aspect of treatment is to keep your pet on consistent flea and tick prevention. These parasites can transmit a number of different diseases, so it is best to protect your pet year-round.
Dogs are not a direct source of infection to people, but they can carry unattached, infected ticks into your house. This can potentially allow them to attach to another person or animal and transmit the disease. In people, typical symptoms include fever, headache, fatigue, swollen lymph nodes, neck stiffness, body aches and rash. The rash that occurs with Lyme disease is described as a target lesion. It is red in the center, followed by a ring of normal-colored skin and another ring of red skin. If you or your pet are showing any of these symptoms, seek medical attention immediately.