Pet Health Information

LYME DISEASE

In 1977 Lyme disease was recognized in a series of children in Lyme, Coon. Soon thereafter the disease was also recognized in the canine. In 1982 the causative agent, a spirochete, Borrelia burgdorferi, was identified as the cause.

 Deer ticks transmit the disease. Regions that have been heavily infected include the Northeast, North central, and western Pacific United States and eastern Ontario , Canada . Although many dogs can be exposed in endemic areas it is estimated that only 5% of exposed dogs will develop clinical symptoms.

 The most common sign is an acute or subacute arthritis. Other signs include fever, anorexia, depression, and limb dysfunction. Often the dog will become suddenly lame in one or more joints or legs. The joints may swell and lymph nodes may enlarge. It may take months after infection to see symptoms. The symptoms may clear without treatment, and recur at future points in time.

 Lyme disease can sometimes affect other body systems. These include the kidneys resulting in renal failure, the heart secondary to myocarditis, the nervous system, and the eyes. The dogs affected by kidney disease usually do not respond to antibiotics and for some unknown reason include a large number of Labrador and Golden Retrievers.

 Tests to diagnose include an immunofluorescent antibody test and an ELISA to document true exposure. Results are interpreted as positive, equivocal, or negative. It is possible for some dogs to test negative and still be in some stage of the disease. Up to 75% may test positive in our area.

 Vaccination complicates the interpretation of these serum titer results. The Western blot technique is used to determine true infection although serodiagnosis remains confusing in its interpretation. Diagnosis is made by excluding other diseases and often by trying a trial of antibiotics. Response to treatment if often rapid and is seen within the first 48 hours. Several antibiotics are used and treatment is continued for as long as 30 days. With kidney involvement, treatment may be needed for several weeks. If a dog relapses, treatment is again initiated. In some dogs there may be an immune-mediated response indicating the need for additional diagnostics and treatment.

 Prevention centers around tick (vector) control. Topical tick preventives are always recommended such as Frontline. Two vaccines are currently available on the market, a whole-cell killed vaccine and a recombinent vaccine. There remains concern that the vaccine in some dogs may trigger autoimmunity. Vaccination of dogs for Lyme disease remains an area of great controversy.

 We do not, at this point in time, recommend universal vaccination for all dogs. Tick control remains the primary mode of control. Treatment for suspected cases remains essential. Dogs that are heavily exposed can be given a vaccination at the owner's request. As the information on vaccination changes we will keep our clients informed of all new and/or additional recommendations.

Lyme disease in people and pets can be treated. Early detection is important. In people the rash is very obvious, in dogs, we are not so lucky. We must wait for signs of illness to develop. You play a vital role in the diagnosis of Lyme disease by knowing when your pet is limping suddenly, or seems to be ill.