Definition:
Pasteurellosis is an infection with a species of the bacteria genus Pasteurella , which is found in humans and animals. Pasteurella multocida (P. septica) is carried in mouth and respiratory tract of several animals, including cats, dogs and rabbits, and some birds and fish. It is a small gram negative bacillus with bipolar staining by Wayson coloration. In animals it can originate fulminant septicaemia (chicken cholera), but is also a common commensal. It is usually harmless, but sometimes it can lead to a disease caused pasteurellosis, which is especially prominent in rabbits (where it known as rabbit flu). Pasteurellosis in humans is associated with a close animal contact, namely a catbite or dogbite.
P. multocida is present in the saliva and faecal material of animals.The most common form of infection in humans is through a bite or scratch, usually from a cat or dog, from an animal carrying the bacteria.Once the bacteria have been passed to a person, there is a possibility that they may go on to develop pasteurellosis. John Freeman was thought to have contracted the infection from the rabbit through a blister on his thumb.
Several hundred people are infected with pasteurellosis each year.But deaths are very rare, according to the Office of National Statistics the last recorded death from pasteurellosis was in 2001.
Types
There are several forms of the infection:
– Cutaneous / subcutaneous disease : this is a septic phlegmon that develops classically in the hand and forearm after cat bite. Inflammatory signs are very rapid to develop, in 1 or 2 hours edema , severe pain and serosanguineous exudate appears. Fever , moderate or very high can be seen alongside with vomiting, headache and diarrhea. Lymphangitis is usual. Complications are possible, in the form of septic arthritis, osteitis or evolution to chronicity.
– Septicaemia : is very rare, but can be as fulminant as septicaemic plague , with high fever, rigors and vomiting followed by shock and coagulopathy.
– Pneumonic disease : is also rare and appears in patients with some chronic pulmonary pathology. it usually presents as billateral consolidating pneumonia , sometimes very severe.
Other locations are possible, like septic arthritis, meningitis and acute endocarditis but are very rare
Pasteurellosis in animals
P. multocida causes numerous pathological conditions in domestic animals. It often acts together with other infectious agents, like Chlamidiae, Mycoplasmae, viruses. The environmental conditions play also a role like transportation, bad weather, housing deficiency.
The following diseases are considered caused by P. multocida, alone or associated to other pathogens :
* Shipping fever in cattle and sheep.
* Enzootic pneumonia of sheep (and goats, with frequent intervention of Mannheimia haemolytica)
* Fowl cholera (chicken and other domestic poultry and cage birds)
* Enzootic pneumonia of pigs
* Pasteurellosis of chinchilla
* Pasteurellosis of rabbits
Symptoms
The first signs of pasteurellosis can occur a few hours after infection, and include pain, redness and swelling around the area of the infection.If the infection spreads and gets into the bloodstream, it can cause flu-like symptoms such as fever, headaches, chills and swollen glands, and if left untreated can result in pneumonia or septicaemia, and on rare occasions, death.
Diagnosis
Diagnosis is made with isolation of Pasteurella multocida in a normally sterile site ( blood, pus or CSF).
Treatment
Pasteurellosis is usually treated with high dose penicillin. Tetracycline and chloramphenicol provides an alternative in beta-lactam intolerant patients.
What should I do if I have been scratched or bitten by an animal?
You are advised to carefully wash the wound, using a disinfectant soap, and to seek medical advice.Immuno-suppressed people are at greater risk of serious complications, as with any infection, so should seek medical advice immediately.
Should I be worried if I keep animals?
Vets urge pet owners not to worry, the bacteria is extremely common and usually harmless, but they say bites or scratches should be treated with caution.
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose
Resources:
http://en.wikipedia.org/wiki/Pasteurellosis
http://news.bbc.co.uk/2/hi/health/medical_notes/5270588.stm