What is Lyme disease? How does my dog get infected?
Lyme disease is an infectious disease caused by bacteria called Borrelia. The bacteria are most commonly carried by the deer tick (also known as the black-legged tick). Infection occurs when a dog is bitten by an infected tick. It appears that the disease is not transmitted until the tick has fed for approximately 12 hours. The tick itself becomes infected by feeding on infected mice, birds, deer, and other animals.
In the United States, Lyme disease has been reported in every state, but over 95% of cases are from the Northeastern, Mid-Atlantic, and upper Midwestern states, with a small number of cases reported along the West Coast, especially Northern California. In Canada, Lyme-positive dogs are found mostly in southern Ontario and southern Manitoba, with a small number of cases in southern Quebec and the Maritime provinces.
Lyme disease, also known as Lyme borreliosis, is a bacterial illness that can be transmitted to humans, dogs, and other animals by certain species of ticks. It is caused by the spiral-shaped bacterium Borrelia burgdorferi that is carried inside a tick and gets into a dog or person’s bloodstream through a tick bite. Once in the bloodstream, the bacteria can travel to different parts of the body and cause problems in specific organs or locations, such as joints, as well as overall illness.
Given the seriousness of Lyme disease, it’s important to be aware of tick prevention and treatment for dogs.
The ticks that carry Lyme disease are especially likely to be found in tall grasses, thick brush, marshes, and woods — waiting to latch onto your dog when he passes by. A tick can transmit the disease once it has been attached to a dog for 24 to 48 hours.
First named when a number of cases occurred in Lyme, Connecticut, in 1975, the disease can be hard to detect and can cause serious, ongoing health problems in both dogs and people.
Lyme disease happens in every state, but infection risks vary. Over 95% of cases are from the Northeast, the Upper Midwest, and the Pacific coast, although with recent changes in deforestation, migrating deer, and bird populations, percentage rates in these areas are constantly changing.
A small number of cases crop up each year along the West Coast, especially Northern California. In Canada, Lyme-positive dogs are found mostly in southern Ontario and southern Manitoba. A smaller number of cases are reported each year in Southern Quebec and the Maritime Provinces.
Which antibodies does the vaccine from Intervet (Merck) induce?
This vaccine is based on recombinant OspA and OspC and is expected to induce antibodies to both of them. The use of this vaccine interferes with the detection of early Lyme infection in vaccinated animals. However, infected animals can still be identified based on OspF antibody values.
Lyme disease in the dog. Dr. Dan explains Lyme disease
Lyme disease is induced by the spirochete B. burgdorferi. Spirochetes are transmitted to dogs by infected ticks. Similar to humans, dogs are incidental, dead-end hosts for B. burgdorferi1 . Typical clinical signs in dogs are sporadic fever, acute arthritis, arthralgia, lameness, and glomerulopathy2-4. Clinical signs of lameness often develop two to five months after infection. B. burgdorferi can persist for at least one year in clinically recovered, untreated dogs3. In a report from 1992, clinical signs of Lyme disease were estimated to occur in 5-10% of seropositive animals5. This percentage likely underestimates the current Lyme disease prevalence for dogs in endemic areas due to a higher awareness of the disease in owners and veterinarians and improved diagnostic methods.
Serum antibodies to different antigens of B. burgdorferi are commonly used to identify dogs that were exposed to the pathogen and to diagnose Lyme disease in dogs with compatible clinical signs2,6-8. Former ELISA based diagnostic tests identified antibodies as early as four to six weeks after infection3. The new Lyme Multiplex assay can identify antibodies to B. burgdorferi by three weeks after infection9. High antibody levels were found in serum of experimentally infected dogs for at least seventeen months3 and are likely maintained for much longer times, i.e. as long as B. burgdorferi persists in the dog.