Contrary to the name, Cat-scratch disease affects people more than cats. The disease is caused by bacteria that is introduced through a cat’s scratch (or bite). The wound caused by the claws and sharp teeth is narrow, deep and therefore difficult to disinfect. Fleas play a major role in the transmission of the disease.
Cat-scratch disease (CSD) or Bartonellosis is caused by Bartonella bacteria. These bacteria live inside the red blood cells of infected cats. Young cats (especially kittens) and strays are the most common carriers of Bartonella.
Fleas bite an animal and take a meal of blood. When biting a CSD-infected cat, a flea can ingest the Bartonella bacteria. If the flea moves to a different cat then it will transmit the bacteria, through biting, to infect the new animal. About 30% of flea-infested cats carry these bacteria. The greater risk of human infection comes from flea-carrying kittens.
Most infected cats show no obvious symptoms. There may be an intermittent fever and in some pregnant mothers, the disease can cause abortion.
In people, suspect infection if the area of the scratch or bite appears red and swollen in three to 10 days afterwards. The injury may develop a lesion with pus inside. The person may experience fever and pain in the lymph nodes nearest to the wound. Typically, healthy people with an infection do not need treatment.
CSD can cause serious complications that may affect the heart, eyes or brain. These are rare and occur in children and in people with weakened immune systems. In such cases, antimicrobial therapy is recommended and generally effective.
Cat-scratch disease can be treated easily, if necessary, with an appropriate antibiotic treatment. Inform your medical doctor about a suspicious cat bite or scratch if symptoms appear.
Always wash your hands, with soap, after playing with your cat. Take care when handling a feral cat. Avoid being scratched or bitten by any cat. Teach children to play gently with all kittens and cats.
Always protect your cat against the risk of fleas. Flea bites can cause itching and can transmit Cat-scratch Disease to your cat and your family. Discuss flea product recommendations with your veterinarian and veterinary team.
Protecting your pet from tick-borne diseases
Roundworms in dogs and cats