This post was contributed by Ron Scharf, veterinarian at the Animal Hospital of Niskayuna.
Spring is here in the Northeast and ticks are out agaian. Dogs are at risk of tick-borne diseases, as we humans are. We are in an endemic area for Lyme disease in our location in the Capital Region of New York State. Getting more common are Anaplasmosis and Ehrlichiosis. These other tick-borne diseases can cause non-specific symptoms such as fever, lethargy and anorexia. Less commonly, we see musculoskeletal pain (such as polyarthritis), organ enlargement and central nervous system signs such as incoordination and seizures.
Much more commonly we see no symptoms, or very subtle ones. “I just thought he was getting older, Doc” is often heard by veterinarians.
All three of these are tested for on a yearly basis by most veterinarians in a test called the 4Dx, in which they accompany heartworm disease testing. This latter condition is a different vector-borne disease in which mosquitos serve as the carrier.
The vast majority of dogs who test positive for any of these tick-borne diseases are asymptomatic. As a matter of fact, up to 95% of dogs who test positive for Lyme disease show no symptoms. The typical way for a Lyme disease dog to show a problem, aside from the non-specific signs mentioned above, is with a limp. This lameness may shift from one leg to another, it does not get better using non-steroidal anti-inflammatory medication, and X-rays do not show any joint pathology.
Most dogs showing these symptoms get better on antibiotics. Doxycycline has been the go-to drug to use but it is not currently available to veterinarians, so we use minocycline instead. Both can cause vomiting, which is less likely if the medication is given with a meal.
The organisms remain in the system for several years, after which the antibody levels detected by the blood test diminish to undetectable levels, unless a new exposure happens.
It is rare for a chronic case to happen in dogs, such as what Tuesday’s book review in the Daily Gazette discusses. It does happen, though. Lyme nephritis, a kidney disease, most commonly in Golden and Labrador Retrievers, is the biggest example of chronic, and heart-breaking, disease.
Diligent tick-control measures are very important. Look carefully through your dog’s coat after being in the woods. And don’t forget that ticks love the October and November weather!