The hidden dangers of cat scratch fever

UNDATED HealthFirst reporter Leslie Toldo tells us about the rise in this illness that may spread to other animals as well.

You may have thought Cat Scratch Fever was the title of a creepy Ted Nugent song.

In reality, it's a contagious infection that some veterinarians are calling an increasing threat.

The neighbor's dog, your kid's cat, the fleas in the front yard. They could all have bartonella, and North Carolina State University Dr. Ed Breitschwerdt, DVM, says that's bad news. "In my opinion, bartonella may prove to be the most important emerging infectious disease of the next decade."

It's an infection linked to heart valve disease, and may have a role in neurologic and arthritic disease. Still, few people even know what it is.

Essentially, it's the bacteria that causes cat scratch disease, but experts say most any animal with claws tainted by flea feces can transmit it, which makes treatment tough.

"The organism changes its nature, its outer surface, again, so that the immune system cannot eliminate it," explained Breitschwerdt.

According to the University of Iowa and the CDC, 40 percent of cats carry bartonella at some point. With 24,000 annual cat scratch cases, up to 90 percent of those affected will suffer a rash, nausea and weight loss. Less than 20 percent could see sensory loss, pneumonia or encephalitis.

"Understanding transmission is of critical, critical performance," Breitschwerdt stressed.

While bartonella can circulate in the blood of cats and dogs, it can cause tumor-like lesions in people. It's tough to detect because it stays in human blood in very low levels.

"I think in the context of bartonella, I think there's many, many more questions right now than answers," Breitschwerdt said.

With research now including sick dolphins and whales, Breitschwerdt says you need to be concerned now.

BACKGROUND: Cat Scratch Disease (CSD) can occur after one comes in contact with the dangerous bacteria Bartonella Henselae, which is transmitted from the lick, bite or scratch of an infected cat. Kittens are more likely to carry the bacterium, but roughly 40% of all cats carry it at some point in their lives. The cats pick up the bacterium from predatory fleas carrying it, but it has yet to be determined if those fleas can directly infect humans. The infection is hard to detect in cats, because they exhibit no external symptoms following transmission. The disease is becoming increasingly common, with 24,000 cases reported each year. (SOURCE: cdc.gov, kidshealth.org)

SIGNS AND SYMPTOMS: After developing a mild infection from the injury, victims of CSD typically experience fever, fatigue, headache or a diminished appetite. A blister called an inoculation lesion, often mistaken as a bug bite, may develop on the victim's arms, hands, head or scalp days after the scratch or bite. There is typically little to no pain associated with the lesion. Within weeks, head, neck and upper limb lymph nodes often become swollen and tender, the area of the infected lymph node being directly related to the location of the lesion. Most frequently, swollen lymph nodes are located in the armpit or neck area, but a leg lesion will cause swelling of the groin nodes. The skin covering the lymph nodes develops a red hue, and sometimes leaks pus. In highly rare cases, liver, spleen, bone, joint or lung infections, and even brain inflammation and seizures, have occurred without any previous symptoms. HIV/AIDS, cancer and organ transplant patients are at the highest risk of experiencing such complications due to their weakened immune system. (SOURCE: kidshealth.org)

TREATMENT: Antibiotics are most commonly used to fight the disease, and should be regulated on a strict schedule. Nonprescription medicines such as acetaminophen can be used to reduce fever or any pain from swollen lymph nodes. The swelling of lymph nodes can take anywhere from 2 to 4 months to subside. (SOURCE: Penn State Children's Hospital A-Z Topics)

HOW TO REDUCE RISK OF INFECTION: An important provision any cat owner should consider is to have the cat declawed. Preventative measures include avoiding any interactive activities that may provoke aggressive behavior from your cat, removing fleas periodically and washing your hands after any contact with a cat, especially if you were scratched or bitten. It is important to instruct children to stay away from stray and unfamiliar cats. (SOURCE: familydoctor.org, Penn State Children's Hospital A-Z Topics)

For more information:

Tracey Peak
North Carolina State University
919-515-6142
Tracey_peake@ncsu.edu



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