Have you ever heard of Lyme disease in pets? 

Many people have heard of Lyme disease, but its effects on pets are often overlooked. In the United States, this disease is primarily caused by the bacteria Borrelia burgdorferi, with Borrelia mayonii also contributing in some cases. These harmful bacteria are spread through the bites of infected ticks, posing risks to both humans and animals.¹

Diagnosing Lyme disease involves recognising key symptoms, conducting thorough physical examinations, and considering potential exposure to tick-infested areas. As you read this article, you will gain a deeper understanding of Lyme disease, its impact on pets, and how you can take proactive steps to protect your furry companions and your household.

Risks of Lyme disease for pets

Transmission risk

Both dogs and humans are at risk of contracting Lyme disease if bitten by a black-legged tick carrying the infection.² These ticks are incredibly small, making them easy to overlook. Nymphs are about the size of a poppy seed, while adults resemble sesame seeds. Since the bacteria can be transmitted within 24 to 48 hours, promptly removing ticks is essential.

The risk of transmission is highest from spring through fall when nymphs and adult ticks actively seek hosts. However, infections can occur year-round. In certain regions of the United States, more than half of black-legged ticks have been found to carry Borrelia burgdorferi.

How does my pet get a tick?

Contrary to popular belief, ticks do not drop from trees onto their hosts.² Instead, they climb to the tips of grasses or shrubs and adopt a posture called "questing," where they extend their front legs to latch onto animals or people who brush past. Understanding this behaviour can help pet owners take effective preventive measures, such as avoiding tick-prone areas and performing regular tick checks.

What about other pets?

While dogs are the most commonly affected pets, cats are not entirely immune to Lyme disease, though cases are relatively rare. Cats that roam outdoors, particularly in tick-heavy areas, can be exposed and should be monitored for signs of illness, such as lethargy or loss of appetite. Preventive measures like tick control treatments and regular grooming are essential for feline companions. 

Other animals, such as horses, can also contract Lyme disease. Infected horses may exhibit symptoms like lameness, stiffness, or behavioural changes. Pet owners with a variety of animals should consult their veterinarians for specific preventive strategies tailored to each species.

Symptoms of Lyme disease in pets

Most pets infected with Borrelia bacteria remain asymptomatic, displaying no signs of illness.² In contrast, about 90% of infected humans will develop noticeable symptoms. However, when symptoms do appear in for example dogs, they typically surface two to five months after the initial infection, by which time the disease may have spread extensively within the body.²

It is crucial to monitor pets closely for these signs and seek veterinary care promptly if Lyme disease is suspected. Early diagnosis and treatment can prevent complications and improve outcomes for affected animals. Common signs of Lyme disease in dogs include:^2,3

• Limping or lameness that may come and go
• Fever
• Loss of appetite
• Reduced activity levels
• Swollen lymph nodes
• Painful, swollen joints

In more severe cases, Lyme disease can lead to a serious kidney condition known as Lyme nephritis. Symptoms of this condition include:^2,3

• Edema (swelling)
• Weight loss
• Vomiting
• Diarrhea
• Potentially, death if left untreated

Preventive measures for Lyme disease in pets

Prevention is better than cure! If you own a pet, it is important to be vigilant about ticks, as they can affect both your pets and you. Dogs, outdoor cats, and horses are at higher risk for contracting Lyme and other tick-borne illnesses from ticks infected with Borrelia burgdorferi, the bacterium that causes Lyme disease.

To protect your pets, avoid letting them freely wander in grassy, wooded areas known to be infested with ticks.⁴ Inspect your pet’s skin and fur thoroughly every day for ticks, especially during peak tick seasons.

Symptoms of Lyme disease or other tick-borne infections might not appear until weeks or even months after a tick bite. Therefore, it is crucial to have your pet checked by a veterinarian if ticks are discovered, even if they show no immediate signs of illness.

If you live in a region with a high prevalence of Lyme disease, such as Canada, the US Northeast or Midwest, your veterinarian may recommend vaccinating your pet against Lyme disease.^4,5 Additionally, using veterinarian-approved tick prevention products, such as collars, topical treatments, or oral medications, can significantly reduce the risk of infection.

Summary

Lyme disease poses a significant threat to pets, especially in areas where ticks carrying Borrelia burgdorferi are prevalent. While dogs are most commonly affected, outdoor cats, horses, and other animals are not immune to the risk. Symptoms may remain hidden for months, making vigilance and preventive measures essential.

Protecting your pets starts with regular tick checks, avoiding tick-heavy environments, and using veterinarian-approved prevention products. Vaccinations can provide added protection for dogs in high-risk regions. By staying proactive and informed, pet owners can significantly reduce the risks of Lyme disease, ensuring the well-being of their furry and feathered companions.