Cat Scratch Disease
Cats are now the number one pet in North America, and with good reason. Small, clean and hardy, they make wonderful household companions. Unfortunately, some cats carry an organism called Bartonella henselae, which can cause Cat Scratch Disease. CSD isn't common, but it affects mostly children. Usually the symptoms are mild, but for anyone with a weakened immune system, CSD can be extremely serious. Understanding how CSD is transmitted and recognizing the symptoms will help protect children from contracting it.
Five-year-old Andrew loved wrestling with his new kitten, and his mother wasn't surprised to see little hair-line scratches up and down her son's arms -- they both liked to play rough, and she figured it would teach Andrew to be gentle. What she was surprised to discover however, was that those "learning experiences" put her son at risk of developing Cat Scratch Disease.
Caused by a tiny organism called Bartonella henselae, Cat Scratch Disease is a zoonosis: a disease that can be transmitted between humans and animals. In this case, cats infected with Bartonella don't become ill themselves; they simply act as reservoirs for the organism. Researchers believe Bartonella is spread between cats by fleas that jump from cat to cat, inoculating with every bite. Kittens are more susceptible to contracting the organism than adult cats, and owners of kittens infested with fleas are 29 times more likely to develop Cat Scratch Disease than people with flea-free cats.
The risks of humans contracting CSD are small. Not all cats carry the organism, and not all people who live with a carrier cat will be infected. Research published in the December 1998 Compendium of Veterinary Medicine shows that only 25 to 40 percent of pet cats are carriers. In 1993, the incidence of Cat Scratch Disease was listed at less than one case per 100,000 people, but here's the significant fact for parents: the majority of those cases were in children between 5 and 14 years of age.
Most people who contract this relatively rare illness experience only minor symptoms. The first sign of Cat Scratch Disease, according to Dr. Diane McKelvey, author of The Safety Handbook for Veterinary Hospitals, is a scratch on the hand or forearm that develops a small blister resembling an insect bite. "Normally, this lesion resolves in a few days to weeks," she says. "However, lymph nodes near the scratch may become swollen and tender."
Most sufferers will not even know they are ill, but about 30 percent of patients will experience flu-like symptoms: headache, fatigue, muscle soreness and fever. These usually clear up on their own after several weeks, fortunately, because also like flu, there is little treatment available. Pain medication, rest and hot compresses applied to the affected lymph nodes are the usual recommendation. The neurological symptoms -- headache, fever and confusion -- occur more commonly in children, many of whom also develop seizures. Although these symptoms are more dramatic, long-term consequences are still rare and recovery is usually rapid.
In spite of its benign appearance, Cat Scratch Disease can be a more serious illness for a small number of sufferers, most of who are unable to fight the organism because of a compromised immune system due to previous illnesses. For this reason, up to 10 percent of those who contract the illness will develop complications such as conjunctivitis, tonsillitis and inflammation of the brain.
Does this mean immune-deficient people shouldn't own cats? Not necessarily. Since outdoor kittens with fleas are the most likely to carry Bartonella, precautions are easy. Minimize the risks by adopting an older indoor feline from known source (such as a reputable breeder who practices good health care and parasite control), instead of a stray kitten. Avoid shelter cats and kittens, as these are most likely to have had contact with feral or wild cats. Feral and stray cats carry heavy flea loads and present a likely method of transmission to housecats.
But what if you already have a cat? If you are concerned about the possibility of CSD, or if you or someone in your home is immune-compromised, talk with your doctor and your cat's veterinarian. You might consider buying peace-of-mind by requesting blood cultures and serology for Bartonella antibodies in your cat. Although these tests are not widely available, your veterinarian can send the samples to a laboratory that performs this service. Antibiotics are an option for cats with positive results, though this is not a guaranteed treatment, and repeated blood tests are necessary over several weeks in order to determine success. A negative test result indicates that the cat is not a carrier of Bartonella, and will not be able to transmit CSD to his owner.
For those of us who already have and love our cats,
the best way to prevent Cat Scratch Disease in our
children is common sense and good education.
- Teach your children to thoroughly wash all bites and scratches as soon as they occur, and never allow cats to lick the open wounds (ouch!).
- Show children how to play gently with their pets, using toys for wrestling, instead of hands. Accustom your kitten to gentle handling and reward her with treats of catnip or special toys when she plays nicely.
- Keep your cat indoors and don't allow contact with strange cats.
- Train him to accept regular nail trims right from the start.
- Most importantly, ask your veterinarian to recommend the best flea control products available to maintain a flea-free home.
Proper hygiene, parasite control and behavior modification are part of responsible pet care for every pet owner, especially parents who want to raise conscientious pet-loving children. Cat Scratch Disease is still considered uncommon. Most people -- cat owners and otherwise -- will never develop illness caused by Bartonella; healthy pet owners have no need for special precautions when interacting with their feline friends. So use good sense and don't be afraid to let your children love pets. It's worth it!