Questions and Answers
April, 1999
October 14, 1998
Dear Dr. Silverio,
Who are the manufacturers of the Lyme’s disease vaccine for
dogs? I believe my dogs have been receiving one made by Fort
Dodge but I have heard there is a newer one which is better.
Could you explain the difference in the vaccines to me?
Thank You,
Patsy Holmes
Canine Lyme Disease Vaccination
The first vaccine against canine Lyme disease received a
conditional license in 1990. This product, Lymevax (by Fort
Dodge), has undergone much testing since then. Although it does
seem to offer some protection in areas where the disease is
prevalent, some have incriminated this vaccine for possible
auto-immune reactions. These include potentially serious signs
produced when the immune system over-reacts to stimulation.
The first vaccine to challenge the Fort Dodge product was Galaxy
Lyme (now offered by Shering-Plough). This vaccine produces
antibodies against a second strain of the Lyme disease organism,
as well as the first strain. However, there is still some
question as to the importance of this second strain. It may not
be responsible for a significant number of cases of Lyme disease
in dogs.
Both of these vaccines are produced from bacterins, or killed
bacteria. When administered to a dog, antibodies develop against
a number of antigens. An antigen is any protein that elicits an
immune response, and there are many antigens on the surface of
any disease-causing bacteria or virus. These bacterins, then,
will stimulate production of antibodies against many antigens.
Antibodies against certain antigens may be very effective at
fighting off the disease when true infection occurs. Antibodies
against other specific antigens may be less effective. More
importantly, some antigens may actually be more likely to cause
undesirable side effects, such as symptoms of the disease or
auto-immune reactions. The ideal vaccine would contain only those
antigens that produce good immunity with minimal side effects.
This is the basis for the newest vaccine, Recombitek Lyme (by
Merial). It contains a single antigen, called OspA. This is the
antigen being used to develop a human Lyme vaccine, because it
seems to create an immune response that is both protective and
safe.
To maximize the safety and effectiveness of vaccination against
Lyme disease, the vaccine should be given before any exposure to
the disease. If you live in a high-risk area, it is best to start
the vaccination when your dog is still a puppy and repeat it
every year. If the dog’s first vaccine is to be given after
possible exposure to infected ticks, consider a blood test that
checks for the presence of antibodies to the disease, before you
vaccinate. The test may give the most reliable results if done
several months after exposure. Therefore, testing during the
winter months is advised, when this is possible.
If you live in an area where Lyme disease is not common, ask your
veterinarian if he or she feels the likelihood of a vaccine
reaction is greater than the threat of the disease.