Thursday, February 26, 2009

Lyme's disease

We have to be very aware of ticks and their danger here in our area. They are just a fact of life on our wooded acres. Had heard about a new test for dogs that was reasonably priced, the C6 test. We plan to ask our vet about it so that if one of our dogs begins to show symptoms, we can be prepared.

Here is an informative article about dogs and lyme's disease. See the whole article here.

A snippet:

"A dog with symptoms of Lyme disease ideally should have a test to confirm or rule out Lyme disease. Since it is almost impossible to culture the Lyme spirochete, efforts have centered on detection of antibodies against the Osps. The problems encountered with this method are:

  • In a Lyme endemic area, as many as 90% of the dogs will have antibodies against the Lyme spirochete. Most exposed dogs never get sick but almost all of them will develop antibodies and these antibodies persist for years. How do we tell the dogs that have active infection from those that have been exposed and are not sick from their exposure?
  • Vaccine has been available for Lyme disease for a decade or more. How do we distinguish antibodies generated by the vaccine from those generated by natural infection?
  • How do we distinguish antibodies generated by similar organisms (Leptospira, for example, or harmless other Borrelia species)?

The solution to these problems has come about only recently in the form of the C6 test. This is an immunological test for antibody against the C6 peptide, a unique section of the one of the Borrelia burgdorferi surface antigens. As the spirochete changes its configuration to escape the host's immune system, the C6 peptide remains constant and always detectable. Vaccine does not contain the C6 peptide so vaccinated dogs will not test positive. Dogs with other infections will not erroneously test positive. Further, this test is simple enough to be available as an in-house test kit (the IDEXX Snap-3 Dx test), which can be run in most veterinary hospitals with results in approximately 10 minutes.

This still does not address distinguishing active infection from exposure. Dogs will test C6 positive within to 3 to 5 weeks of infection. They stay positive for over a year.

Treatment and Its Goals

Which of these dogs get sick and which do not? Does the dog with joint pain, fever, and a positive C6 test need medication? This is where the news is particularly good.

Treatment of Lyme disease utilizes a 2 to 4 week course of doxycycline, a medication that is inexpensive and has limited side effects potential. Amoxicillin is another effective alternative, also inexpensive and with minimal side effects. If Lyme disease is a consideration, many veterinarians simply prescribe the medication. Obvious improvement is seen within 48 hours. Furthermore, most tick-borne infections capable of causing joint pain, fever, and signs similar to Lyme disease generally are all share responsive to doxycycline so a simple course of medication actually covers several types of infection.

Eradication of the Lyme spirochete is not a reasonable expectation with treatment; the organism is simply too good at hiding. The goal instead is to bring the patient into what is called a premunitive state. This is the state that 90% of infected dogs achieve when they get infected but never get ill: the organism is in their bodies latently but is not causing active infection."

No comments:

Post a Comment