Lyme disease (dog)
Many dogs have antibodies against Lyme disease in the blood. Some sick and many healthy dogs test positive. When dogs are injected with the Lyme bacteria, they usually do not get sick. How valuable is a positive test?
A story about a controversial bacterium.
Lyme disease in humans
Lyme disease is caused by the bacterium Borrelia burgdorferi. A large part of the Dutch ticks is infected with this bacterium and can transmit the infection: on humans and dogs.
About 90% of people who become infected with Borrelia become ill. They get flu-like symptoms, painful joints and a red, circular inflammation around the spot where the tick has bitten (erythema migrans). Some people get heart problems, neurological problems or chronic skin changes.
Lyme disease is transmitted by a tick.
People can not get Lyme disease directly through the dog or cat.
Make the tick dead after removal so that this tick can no longer infect anyone.
Dogs do not seem sensitive to Lyme disease
Experimentally infected dogs did not become ill. Only some experimentally infected puppies received symptoms. After infected ticks were put on the dogs, they got a fever, a bad appetite or joint inflammation. A few months after infection the puppies showed a joint inflammation in the leg that was closest to the tick bite. The disease disappeared without treatment. Some weeks later, puppies showed signs of joint inflammation in the same leg or in another.
Dogs are sensitive to Lyme disease?
In several studies it is described that dogs that develop Lyme disease “in the field” may show signs of kidney problems, neurological symptoms or skin changes.
– Joint complaints due to Lyme disease?
In our country many (also healthy) dogs have antibodies to Borrelia burgdorferi (seropositive). It is therefore difficult to say whether joint complaints are actually caused by Lyme. However, it appears that dogs with polyarthritis (inflammation of multiple joints) test seropositively for Borrelia burgdorferi more often than healthy dogs (for example, demonstrated with Retrievers), but that probably does not apply to all breeds.
– Kidney problems due to Lyme disease?
There is kidney disease, which is attributed to Lyme disease. The disease is associated with protein loss via the urine (proteinuria). Other kidney diseases can also cause proteinuria, so here again the question is whether the Lyme bacteria is really the cause of kidney disease. There are so many healthy animals where we also find the Lyme bacteria, without kidney problems. Kidneys can be damaged by antibodies. Perhaps the hereditary predisposition, the defense against some Borrelia burgdorferi strains, along with perhaps other factors, determine whether or not a dog becomes ill.
Why do not practice and experiment match?
It is not known why it is not possible to induce the disease in the laboratory, which is supposed to occur in practice. Perhaps that is because only some varieties are sensitive, or that there are other Borrelia burgdorferi strains in the field than those used in the experiments. Perhaps it is because “in the field” dogs can get multiple tick bites in a row. Or is it perhaps because a dog only becomes ill from the Lyme bacteria, if another infection (with another parasite or bacterium) takes place at the same time?
However, it could also just happen that dogs just do not get sick of the Lyme bacteria.
Consider another cause for the complaints
A positive test for Lyme disease is therefore controversial. Dogs with a “difficult to treat Lyme disease” may have a different cause for the symptoms. The veterinarian must continue to look for a possible other explanation of the problems. What else could be wrong except Lyme?
Dogs with fever, lameness and poor appetite or protein in the urine can have many other diseases. We have to realize that every sick dog can be HIV positive by coincidence, but that does not mean that the dog is really ill because of the Lyme bacteria. Dogs that were referred to us because of “difficult to treat Lyme disease”, often turned out to have something else!
Prevention of infection with Lyme disease
Several Lyme vaccines have been developed, but we do not recommend vaccination with them. Most Borrelia burgdorferi infections do not make the dog ill and sick