By: Trupanion Staff / Published June 16, 2018

Lyme disease in dogs is an issue that all pet owners need to worry about - especially during summer months. When the weather is warmer and your dog spends more time outside, their chances of being bitten by a tick and contracting Lyme disease increase. It’s incredibly common, but symptoms will only show up in roughly ten percent of affected dogs. Even so, the condition is everywhere and can be found on every continent with the exception of Antarctica.

However, ticks carrying Lyme disease can survive in freezing temperatures too! While rare, Lyme disease has been known to cause fatalities, and we will look at why that is a little further down.

What is Lyme disease?

Lyme disease is caused by an organism called Borrelia burgdorferi which can be transmitted to a dog by a tick bite. Lyme disease in dogs is primarily spread during tick season, which is May through August, however ticks are active throughout the year so long as temperatures are above freezing. It is important to note that Lyme disease also affects humans, however it cannot be transferred directly from a dog to a human, although a dog could transport unattached ticks, which later attach to humans.

In 2013, for example, 95% of human Lyme disease diagnoses were made in 14 states: Connecticut, Delaware, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, Virginia, and Wisconsin. These correspond with the distribution of the Ixodes tick vectors. Smaller pockets of infection occurred in central-northern coastal California, near Seattle and along the Florida coast.

How Lyme disease in dogs occurs

Also known as Lyme borreliosis, this disease is transported and delivered by hard-shelled ticks which can be found all over the country, although it is more common in some parts of the country than others.

A tick can latch onto your dog anywhere, but they will typically be found on the underbelly of your animal. To avoid Lyme disease in dogs, you should do a thorough check of your dog once daily to make sure no ticks caught a ride. Transmission of the organism from the tick requires a minimum of 48 hours.

What do the ticks look like?

One of the problems with ticks is that they are difficult to see. Tick nymphs are tiny, just 2mm in length. However, as they feed, their bodies swell, and they become far more noticeable. This means that you will be able to find them on your dog's skin if you look carefully. The issue is removing the tick.

You can remove a tick with a special device that you can get from your vet. Removing it without a tool like this may cause you to only get the body or could force partially digested blood back into your dog which could increase their risk of infection. Be careful and if in doubt, consult your vet.

What are the signs of Lyme disease in dogs?

The most common (and sometimes only) sign of Lyme disease in dogs is sudden lameness which can often appear in one leg and shift to another. Other indications include:

• Swollen or painful joints
• General weakness
• Fever
• Lethargy
• Loss of appetite
• Kidney problems

In rare cases, serious issues such as kidney failure can occur. It is at this point that Lyme disease can become life-threatening for your dog. That’s why you need to make sure that you are getting them checked out as soon as you notice these symptoms.

Neurological and heart issues may also be present in some dogs, but are very rare.

How is Lyme disease in dogs diagnosed?

A common test that veterinarians use checks your dog for antibodies to this disease. Antibodies are created by the body to fight the organism, and a positive result will show the dog was exposed. If positive, additional testing may be recommending.

Treating Lyme disease in dogs

Your vet will be able to provide several treatments for your dog if they have Lyme disease. They may provide antibiotics that can be taken for several weeks. A persistent infection with a very low bacterial burden may remain, but treatment does significantly improve symptoms. In this situation, long-term monitoring may be recommended by your vet.

Is Lyme disease in dogs contagious?

It’s not possible to get Lyme disease directly from your dog. However, the tick that infected it may have been brought into your home.