From humans to cats: learning more about Lyme disease in felines

4 August 2020

Posted by: Mia Rozenbaum

Category: Research & medical benefits

Because cats are rarely affected by Lyme disease, the pathology in felines has remained largely unknown, and the more subtle affliction overlooked. Studying how the disease affects humans has led scientists to take a closer look at the cardiac symptoms in cats and identify for the first time an inflammation of the heart tissue linked to the pathology.

Lyme disease afflicts dogs much more frequently than cats. While cats can become infected, the disease us rarely symptomatic and the animal does not need treatment, unlike an infected human or dog would.

But because Lyme disease has the potential to be a severe condition and is common among humans and dogs, it is also important to know how the disease is transmitted, as well as the signs of infection in our feline companions.

Lyme borreliosis, also known as Lyme disease, is caused by a group of spirochete bacteria transmitted by the bite of a tick. It is a well-established cause of morbidity and mortality in humans. 

ticks.png

Ticks are small creatures that can be easily overlooked, especially when concealed in a pet's fur! 

 

The disease, to this day, remains quite elusive. Symptoms in humans can appear sometimes two to three months after the tick bite. And when they do appear, they are as non-specific as high fever, decreased appetite and general listlessness. In rare cases the disease progresses into an inflammation of the joints, stiffness, pain and an affliction of the kidneys and heart.

However, most cases remain undiagnosed, since they are largely asymptomaticor barely symptomatic, and therefore the description of the pathology remains incomplete. And even more so in cats.

So researchers tried to find out if cats developed similar cardiac symptoms to the ones that dogs and humans do. 

In about 1 to 10% of patients with Lyme disease, humans develop carditis, an inflammation of the heart tissue. In dogs, suspected cases of Lyme carditis exist but are rare. Sudden death from myocarditis or dilated cardiomyopathy are more common. So identifying Lyme disease-linked carditis in cats was notstraight up obvious

However, the researchers did end up identifying for the first time two suspected cases of Lyme carditis in cats, one of which is the first feline case ever resolved after treatment. The two cases in B burgdorferi positive cats with cardiac abnormalitiesthereforeshowa consistency with the disease in humans and dogs. 

The researchers say it is likely that new cases of Lyme carditis will appear in cats, as most practitioners currently do not test for B burgdorferi in cats with heart abnormalities. As the practice becomes more common, so will the number of examples, and knowledge on the matter will increase

A lot more information is needed to fully elucidate the nature of the growing threat that is Lyme borreliosis in cats.

As global warming increases the overall prevalence of ticks on the planet, and their territory expands further North, so will tick-borne infections. More and more cases of the disease are expected. So better be prepared.