Cat-Scratch Disease

Cat-scratch disease(CSD) is an infection caused by Bartonella henselae bacteria found in cats.  It is also known as cat-scratch fever, Bartonellosis, Teeny’s disease, subacute regional lymphadenitis, and inoculation lymphoreticulosis.  Cat-scratch disease is widely found across the globe, particularly in warm humid regions.  In parts of the world with four seasons, CSD occurs more often in autumn and early winter coincides with the rise of midsummer kitten births and flea infestation.  The Bartonella organism has been isolated from fleas residing on infected cats. It can be found in flea feces and in the bloodstream of kittens. Studies have shown that in the absence of fleas, infected cats do not transmit the infection to uninfected cats.  In America, about 40% of the cat population is carrying this bacteria, but rarely are they sickened by it. CSD is generally a harmless disease and requires limited medication if any.

Causes:
Cat-scratch disease is usually spread by infected cats or kittens.  A skin breaking bite or scratch by a cat, exposure of mucous membranes such as eye, nose, mouth to feline saliva, or having open wound licked by a cat, are all possibilities that can lead to cat-scratch disease.  It is commonly found in children within two weeks after getting a scratch or bite from a cat, particularly a kitten.  House cats/kittens can be just as infectious as stray cats.  Luckily, cat-scratch disease is not contagious from one person to person. Furthermore, a fully recovered patient, especially a child or young adult, usually acquires long-term immunity.

Signs and Symptoms:
A CSD infected person may show the following common symptoms, including:

  • Blister or bump at scratch or bite wound site
  • Lethargy
  • Fever
  • Headache
  • Chills
  • Sore, swollen lymph node nearest to the site of scratch or bite
  • Enlarged spleen(upon physical examination)
  • General feeling of unwell
  • Abdominal pains
  • Sore throat
  • Muscular or joint pains
  • Loss of appetite

It may take more than two weeks for symptoms to appear.  Most CSD cases are not serious and medical treatment may not be needed, but swollen or tender lymph glands may linger for several months after other symptoms have disappeared.  With sufficient rest and proper care, the disease usually run its course in about four to five weeks.  In people with weakened immune system, treatment with prescribed antibiotics usually can expect a full recovery.

Complications:
In rare cases, CSD can lead to serious complications, such as:

  • Encephalopathy, an altered mental state
  • Meningoencephalitis, an inflammation of the brain membranes
  • Optic neuritis, an inflammation of the optic nerves
  • Osteomyelitis, a bone infection
  • Parinaud’s syndrome, abnormalities of eye movement and pupil dysfunction

In early 2015, an Ohio woman was left blind in one eye after contracting the disease from her affectionate licking cat.  These rare complications are more likely to occur in children younger than 5 years old and people with compromised immune systems.  Patients with HIV and others with severe immune system dysfunction may be vulnerable to other complications, such as:

  • bacillary angiomatosis, a form of vascular lesions, or
  • bacillary peliosis, blood-filled cavities in spleen or liver.

Treatments:
Most people with a healthy immune system can expect a full recovery from CSD with sufficient rest and consume easily digestible nutritious food.  The attending physician may prescribe antibiotic for persons with weaker immune systems or young children.  Azithromycin, doxycycline, gentamicin, ciprofloxacin, rifampicin, and trimethoprim/sulfamethoxazole are some of the medications to treat a more severe form of CSD.

A pregnant woman is likely to be prescribed with Azithromycin to avoid harming the development of the embryo or fetus.  Individual with optic neuritis complications is better with Doxycycline for its penetrability of the tissues of the eye and central nervous system.

Prevention:
Always wash hands thoroughly with soap and running water after playing with a cat or any animal in general.  Do not handle cat roughly or attempt to cuddle/touch an unwilling cat to prevent getting scratches and bites.  If scratch or bite does occur, wash affected point with soap and running water as soon as possible.  Avoid petting or touching stray or feral cats.  If feline saliva gets into an eye, rinse the affected eye with eye wash immediately.  Do not let cat licks any open wound, no matter how slight the wound may seem.  Keep pet’s flea infestation in checked with scheduled application of veterinarian-approved flea control medication or flea collar wearing.  Frequent carpet, sofa vacuuming/wash is recommended.  Change bedding frequently if the cat is allowed to go on to the bed.  Encourage house cat to claw on cat scratch post or cat scratch board to keep claws shorts.  Invest in a few cat toys with sticks or strings to avoid accidental scratches or bites on your fingers.  Seek medical attention if wound is not healing or unusual symptoms surface

Cats are delightful animals to have around. It is not necessary to ban cats from one’s life for fear of contracting diseases. Like most common contagious diseases, general hygiene observations are adequate to prevent catching cat-scratch disease.