Cat-Scratch Disease
- Cat-scratch disease is a bacterial disease
that results from a scratch or bite by a cat.
Persons with cat-scratch disease can have
a range of illnesses from mild to severe.
- Cat-scratch disease usually causes swollen
lymph glands near the site of the scratch
or bite.
- Most people get better on their own in about
3 weeks.
- To prevent cat-scratch disease, avoid provoking
cats and kittens. Thorough cleaning of cat
scratches and bites might also help.
What is cat-scratch disease?
Cat-scratch disease is an infectious disease
that results from a scratch or bite by a cat.
Persons with cat-scratch disease can have a
range of illnesses from mild to severe.
What is the infectious agent that causes
cat-scratch disease?
Cat-scratch disease is caused by Bartonella
henselae, a bacterium.
Where is cat-scratch disease found?
The bacterium that causes cat-scratch disease
is found in all parts of the world. The bacterium
is carried by cats and kittens. Infected animals
do not become sick.
How is cat-scratch disease spread?
The disease is spread by a scratch or bite
from a cat, most often a kitten. The infection
spreads from the site of the scratch or bite
to the lymph glands. Cats that spread the infection
do not look sick. The infection is not spread
from person to person.
What are the signs and symptoms of cat-scratch
disease?
A blister or sore, with or without pus or fluid,
often shows up on the skin at the place where
the bacteria entered the body. Within 2 weeks,
the lymph glands nearby usually become swollen
and tender. In most children and adolescents,
swollen glands are the main symptom. Adults
often have other symptoms such as low fever,
tiredness, headache, and loss of appetite. About
5% of persons with cat-scratch disease develop
irreversible retinitis (inflammation of the
retina of the eye) or encephalitis (inflammation
of the brain). Persons with weakened immune
systems can become more seriously ill.
How soon after exposure do symptoms appear?
It usually takes 3 to 10 days for a sore to
appear at the site of a cat scratch or bite.
The lymph glands nearby usually start to swell
about 2 weeks after the scratch or bite.
How is cat-scratch disease diagnosed?
Diagnosis is based on symptoms and a history
of a scratch by a cat. A blood test can confirm
the diagnosis.
Who is at risk for cat-scratch disease?
Anyone can get cat-scratch disease. Most cases
are in children and adolescents. Persons who
own or handle cats are at increased risk.
What complications can result from cat-scratch
disease?
In rare cases (1%-5%), cat-scratch disease
can cause complications such as an irreversible
inflammation of the eye or seizures (convulsions).
What is the treatment for cat-scratch disease?
Most people recover on their own within 3 weeks.
Tenderness and swelling can be relieved by putting
warm soaks or a heating pad on the sore area.
Persons with severe pain or symptoms are sometimes
treated with antibiotics. A doctor may need
to open and drain painful, red lymph glands
that contain pus.
A veterinarian should be contacted about the
cat or kitten that caused the infection. Steps
to minimize scratching and biting should be
taken. Cats with cat-scratch disease do not
need to be destroyed.
How common is cat-scratch disease?
In the United States, about 24,000 persons
get cat-scratch disease each year. Most are
children and young adults.
Is cat-scratch disease an emerging infectious
disease?
Yes. The disease was recognized recently, and
the bacterium that causes it was recently isolated.
Cats are one of the most frequently kept pets
in the United States, numbering more than 60
million.
How can cat-scratch disease be prevented?
- Teach children to respect animals and not
to provoke them.
- Do not pick up strange cats.
- Thorough cleaning of cat scratches and bites
might be helpful.