At a recent veterinary seminar that I attended, the speaker discussed a host of infectious problems, including cat scratch disease. This disease has been known as a clinical problem for more than 100 years, but the actual infectious agent was only identified within the past 20 years. Bartonella henselae is the bacteria that causes infections in people from cat wounds.
Just after I graduated from veterinary school, Ted Nugent's song "Cat Scratch Fever" was popular. Mention it and everyone my age starts to sing the song in their head. The disease is quite serious, however. There are 22,000 cases each year in the United States.
In the majority of cases, a small red bump called a papule or a pustule is noted within a few days of a cat scratch or bite. The scratch may progress to a non-healing wound. One to seven weeks later, the regional lymph node can swell. Some patients report headaches, fever or malaise; in general, they don't feel well.
A swollen lymph node is very worrisome because of the possibility of lymphoid neoplasia. Often a biopsy is taken to distinguish between the two diseases. A recent study found cancer in 26 percent of the cases in which cat scratch disease was suspected. Children are the most common age group affected. Between 57 and 80 percent of cases are seen in people under age 21.
Bartonella henselea can cause a host of other conditions in people whose immune systems have been compromised, such as those with AIDS or on chemotherapy. In healthy people, it is usually treated with antibiotics. But the routine use of antibiotics for this disease, especially for some immune-compromised patients, is debatable. An experienced medical expert should be consulted.
Kittens are at a greater risk of disease transmission than an adult cat. Fleas are thought to be the way it is transmitted from cat to cat.
Cats with severe mouth inflammation may be suspected of having infection with Bartonella. Antibiotics may decrease the amount of bacteria in infected cats but is unlikely to completely eliminate the ability of the cat to infect humans. In the future, vaccinations for cats may be one way to reduce infections in people.
When contacting stray or feral kittens and cats and cat colonies, people and especially those most at risk should be careful to avoid scratches and bites. In addition to cat scratch disease, rabies is also a potential risk.
Lawrence Gerson is a veterinarian and founder of the Point Breeze Veterinary Clinic. His biweekly column is intended to educate pet owners. Consultation with a veterinarian is necessary to diagnose and treat individual pets. If you have a question you'd like addressed in Pet Points, email firstname.lastname@example.org. Please include your name and municipality or neighborhood.