|
|
Bartonellosis, also known as Cat Scratch Disease or Cat
Scratch Fever, is an infectious disease of humans.
Evidence is increasing that perhaps the cat becomes
infected with the causative organism, but it does not
appear to produce any disease in the cat. Very little is
known or understood about the role of the cat as a
reservoir for this disease.
|
 |
What are the risk factors?
A cat scratch is sometimes, but not always, associated
with this disease. In one study, 99% of patients with
CSD had exposure to cats. An increased risk of
transmission is present when a kitten is involved, as
opposed to adult cats.
Most cases are reported in the fall and winter, but the
reason for its apparent seasonality remains unknown.
What are the clinical signs?
Antibodies are proteins which are produced by the immune
system in response to some stimulus. About 5% of the
United States population is known to have antibodies to
CSD. Interestingly, about 20% of U.S. veterinarians will
test positive for CSD antibodies. Very few of those
testing positive have actually had the disease. The
majority have had inapparent infections or have been
exposed to the CSD organism without any disease
occurring.
This is generally a mild disease in humans. Many people
experience fever, chills, and lethargy which last only a
few days. Unless the skin test is performed or the
organism is cultured, it may be diagnosed as influenza.
However, the more severe forms of the disease will
produce very high fevers, marked lethargy, anorexia, and
swollen lymph nodes, usually in the axillae (armpit) or
groin. The lymph nodes may enlarge to the point of
rupturing or they may need to be opened surgically to
establish drainage and relieve pain.
Is the cause known?
The cause of CSD has recently been identified as a
bacterium called Bartonella henselae. A cat scratch is
not necessary to transmit the organism; contact alone is
sufficient.
The role of fleas and ticks in the life cycle and
transmission of the organism is an area of research
interest at present.
How is it diagnosed?
The organism does not appear to cause disease in the
cat. When humans are infected, the physician may make a
diagnosis based upon clinical signs, exposure to cats,
blood tests, and studies of lymph node biopsies.
What is the treatment?
The appropriate course of therapy will be prescribed by
your physician. In many cases, the disease is
self-limiting and requires little or no treatment. In
others, antibiotics, pain medication, and bed rest may
be indicated.
What is the prognosis?
The disease is usually self-limiting. It runs a course
of several days to several weeks and then subsides.
Can it be transmitted to me or my family?
The cat is involved because many cases of CSD are
preceded by a cat scratch. Our best understanding of the
cat's involvement is as follows:
The cat is almost always a kitten; adults are rarely
involved.
The cat appears to be contagious for only about 2-3
weeks.
Declawing does not appear to decrease the transmission.
The organism lives in the cat’s mouth and can be
transmitted to the paws by grooming.
One should be very concerned about a family member
having CSD. However, indefinitely banning cats from
one's household is generally not warranted. It has been
shown that less than 10% of family members scratched by
the same cat develop the disease. In addition, there has
not been a person recorded as having had the disease
twice.
How is it prevented?
At present, there is no available test to determine
which cats carry the CSD organism. General
considerations are as follows:
Declawing is not generally considered useful since the
organism may be transmitted by contact alone.
When a kitten is involved, the likelihood of spreading
the organism decreases as the kitten matures.
Euthanasia is not indicated because the involved cat is
usually healthy.
If a cat does scratch or bite, wash the wound thoroughly
with soap and water and, if indicated, contact a
physician.
Always contact a physician whenever an immune-deficient
person receives any animal scratch or bite.
|
|
|
|
