Dog Scratching Flea
The war on fleas just got more personal. New research published by the Bartonella research team at North Carolina State University’s College of Veterinary Medicine now connects the Bartonella infection to rheumatoid illnesses in people.

Bartonella is a bacterium found in fleas, ticks and other biting insects. You may be familiar with Bartonella henselae, which causes cat scratch disease (CSD). Add it all together and fleas may be to blame when it comes to certain human illnesses, such as rheumatoid arthritis.

Eye-Opening Flea and Tick Findings

In a study to be published in the May 2012 edition of Emerging Infectious Diseases, 62 percent of nearly 300 people suffering from a variety of rheumatoid illnesses were found to have antibodies against Bartonella, and 41 percent had DNA evidence of the bacteria in their blood. About 85 percent of the patients reported contact with dogs, and 68 percent had comingled with cats. Plus, over 77 percent had been exposed to ticks, and 68 percent stated that they’d been bitten or scratched by an animal.

The patients had been previously seen by a rheumatologist and diagnosed with such illnesses as Lyme disease, chronic fatigue, various arthralgia and arthritis conditions, and fibromyalgia. (Researchers are also concerned that Bartonella may be directly involved in causing illnesses in the cats and dogs that serve as hosts for the bacterium.)

Although the scientists did not evaluate the role Bartonella might play in these diseases, they hope that physicians treating such patients will start to look for Bartonella infections to determine the link between this vector-borne disease and others.

Unfortunately, it isn’t always easy to diagnose bartonellosis. For years, researchers had speculated that it was involved in a wide variety of inflammatory conditions, but they didn’t have tests that were sensitive enough to detect it. But thanks to some advances in technology, we're beginning to look more closely at Bartonella.

Savvy New Way of Testing

Four years ago, a group led by NC State veterinary researcher Dr. Edward Breitschwerdt, DVM, created a special test that finally allowed extremely sensitive and accurate testing for Bartonella in animals and humans. Curious to hear more about this revolutionary work, I spoke to Dr. Breitschwerdt.

“Until recently, CSD was thought to be a self-limiting infection, and historical blood culture techniques were not sensitive enough to detect bartonellosis in immunocompetent dogs, horses or human patients,” explains Dr. Breitschwerdt.

Based on his new findings, Dr. Breitschwerdt concludes that “bartonellosis is a critically important emerging disease for both human and veterinary medicine. Understanding and addressing the many important questions relative to this genus should be a ‘One Health’ priority.”

Dr. Breitschwerdt calls Bartonella “a game changer in the context of fleas as vectors of these bacteria, which can cause disease in cats, dogs and humans — although much more work needs to be done relative to the transmission dynamics of Bartonella to pets.”

What This Means for Pet Owners

So what does all of this have to do with your cat or dog? If you’re not aggressively treating fleas, it could be vitally important to your own health.

“It is possible that one flea could infect a cat, a dog or a human being,” says Dr. Breitschwerdt, adding that humans can contract Bartonella from cats through “flea bites, scratches and potentially bites.”

Fleas are the primary vector for Bartonella. Without them, your cat or dog can’t get infected, dramatically reducing your risk of contracting Bartonella. Bottom line: If your pet is flea-free, there’s a good chance that it won’t pass the Bartonella infection to you.

It’s important to point out that Dr. Breitschwerdt’s findings haven’t established Bartonella as a cause of these diseases — just that it seems to be present in a suspiciously high number of cases. He hopes that ongoing research will pinpoint if and how bartonellosis is involved in systemic inflammatory conditions.

How to Keep Your Pet Flea-Free

When I asked Dr. Breitschwerdt what the single most important thing owners could do to lessen their chances of contracting Bartonella, he didn’t hesitate: “Prevent flea infestations to avoid the cat becoming infected with these bacteria.” Here's how:

Use a monthly flea preventive year-round. To make protection more convenient — and potentially save you money — talk to your veterinarian about a product that prevents both fleas and heartworm disease. And apply year-round flea preventive on your cat — regardless of whether or not your feline is solely an indoor cat.

Track your pet's travels. Pets who are allowed to roam freely may encounter other animals who carry fleas. Whenever possible, keep unsupervised pets indoors or supervise outside access as much as possible.

Bathe your pet. In addition to checking for parasites, regular bathing allows you to scan for skin lesions. Consistent bathing every week or two is especially important during the warmer months, when biting insects are more prevalent.