Pasteurella multocida is reported to be the most common cause of infection following a cat or dog bite or scratch, according to the Environmental, Health and Safety Department of the UCLA.
It is, however, still a rare disease in humans. Only 5 percent of dog bites and 30 percent of cat bites become infected.
Pasteurella multocida is a gram-negative coccobacillus bacteria. It does not form spores. It is part of the normal mouth flora of dogs (66% incidence), cats (70% incidence), and other domestic species, including birds, cattle, pigs, rodents and rabbits. Synonyms are Bacterium mutocodoium and Micrococcus gallicidus.
Bacterium causes different infections in animals
The common name of infection by this micro-organism is avian cholera when it occurs in waterfowl, chickens and turkeys. Cattle, sheep, goats and buffalo get lung infections and bleeding septicaemia from it, pigs get colds, and mice and rabbits snuffles and septicaemia.
It does not cause any illness or disease in dogs or cats. In rabbits, it may cause snuffles, pneumonia, middle and inner ear infection, conjunctivitis and abscesses.
The bacterium may be transmitted by means of bites, scratches or even licks from dogs, cats or any other carrier animals. Infection may occur without any epidemiological evidence of animal contact.
How can you recognise the disease in humans?
The first signs will develop at the wound site, 12 to 72 hours after the bite or scratch. It is commonly associated with acute skin and tissue infections following an animal bite or scratch.
Rare cases of P. multocida meningitis in children may mimic Haemophilus influenzae. A history of pet exposure should alert the physician to this possibility.
Signs may include cellulites (infection in the cells), pain, swelling, and inflammation of the lymphatic vessels, which can be seen as red streaks in the skin adjacent to a focus of the streptococcal infection.
Complications may include septicaemia, meningoencephalitis (inflammation of the brain and its membranous coverings), osteomyelitis (bone inflammation), and inflammation of a tendon sheath, producing pain and swelling.
How high is your risk of infection by this bacterium?
Since P. multocida may be part of the normal mouth flora of dogs and cats, infection may occur following any bite or scratch. However only 5 percent of dog bites and 30 percent of cat bites become infected.
Can it be prevented?
It is best to avoid bites and scratches from dogs and cats. In general, people with animal bite wounds have a high risk for infection, especially those who seek medical attention more than 8 – 10 hours after the injury occurred. People with underlying medical diseases such as diabetes, HIV infection, chronic liver disease, alcoholism or other immunodeficiency conditions, are at increased risk of infection.
If a bite or scratch occurs, prompt first aid treatment is necessary followed by medical treatment. First aid treatment should include cleansing with an antibacterial detergent and irrigation with large amounts of water. Treatment should include tetanus and rabies prophylaxis. (Mari Hudson, Health24)