Pasteurellosis is an infection with a species of the bacterial genus '' Pasteurella'', which is found in humans and other animals. '' Pasteurella multocida'' (

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

''P. m. septica'' and ''P. m. multocida'') is carried in the mouth and respiratory tract of various animals, including pigs. It is a small, Gram-negative bacillus with bipolar staining by Wayson stain. In animals, it can originate in fulminant septicaemia (

chicken cholera Fowl cholera is also called avian cholera, avian pasteurellosis, avian hemorrhagic septicemia. Abraham b. It is the most common pasteurellosis of poultry. As the causative agent is ''Pasteurella multocida'', it is considered to be a zoonosis. Adu ...

), but is also a common commensal. Until taxonomic revision in 1999, ''Mannheimia'' spp. were classified as ''Pasteurella'' spp., and infections by organisms now called ''Mannheimia'' spp., as well as by organisms now called ''Pasteurella'' spp., were designated as pasteurellosis. The term "pasteurellosis" is often still applied to mannheimiosis, although such usage has declined.

Types

The several forms of the infection are: * Skin/

subcutaneous tissue The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and macr ...

disease is a septic

phlegmon A phlegmon is a localized area of acute inflammation of the soft tissues. It is a descriptive term which may be used for inflammation related to a bacterial infection or non-infectious causes (e.g. pancreatitis). Most commonly, it is used in con ...

that develops classically in the hand and forearm after a cat bite. Inflammatory signs are very rapid to develop; in 1 or 2 hours,

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...

, severe pain, and serosanguineous

exudate An exudate is a fluid emitted by an organism through pores or a wound, a process known as exuding or exudation. ''Exudate'' is derived from ''exude'' 'to ooze' from Latin ''exsūdāre'' 'to (ooze out) sweat' (''ex-'' 'out' and ''sūdāre'' 'to ...

appear. Fever, moderate or very high, can be seen, along with vomiting, headache, and diarrhea.

Lymphangitis Lymphangitis is an inflammation or an infection of the lymphatic channels that occurs as a result of infection at a site distal to the channel. The most common cause of lymphangitis in humans is ''Streptococcus pyogenes'' (Group A strep), hemolyti ...

is common. Complications are possible, in the form of septic arthritis, osteitis, or evolution to

chronicity A chronic condition is a health condition or disease that is persistent or otherwise long-lasting in its effects or a disease that comes with time. The term ''chronic'' is often applied when the course of the disease lasts for more than three mo ...

. * Sepsis is very rare, but can be as fulminant as septicaemic plague, with high fever, rigors, and vomiting, followed by shock and

coagulopathy Coagulopathy (also called a bleeding disorder) is a condition in which the blood's ability to coagulate (form clots) is impaired. This condition can cause a tendency toward prolonged or excessive bleeding (bleeding diathesis), which may occur spo ...

. * Pneumonia disease is also rare and appears in patients with some chronic

pulmonary pathology Pulmonary pathology is the subspecialty of surgical pathology which deals with the diagnosis and characterization of neoplastic and non-neoplastic diseases of the lungs and thoracic pleura. Diagnostic specimens are often obtained via bronchoscopic ...

. It usually presents as bilateral consolidating pneumonia, sometimes very severe. * Zoonosis, pasteurellosis can be transmitted to humans through cats. Other locations are possible, such as septic arthritis,

meningitis Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, headache, and neck stiffness. Other symptoms include confusion or ...

, and acute endocarditis, but are very rare.

Diagnosis

Diagnosis is made with isolation of ''Pasteurella multocida'' in a normally sterile site (blood, pus, or cerebrospinal fluid).

Treatment

As the infection is usually transmitted into humans through animal bites, antibiotics usually treat the infection, but medical attention should be sought if the wound is severely swelling. Pasteurellosis is usually treated with high-dose

penicillin Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from ''Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum using ...

if severe. Either tetracycline or

chloramphenicol Chloramphenicol is an antibiotic useful for the treatment of a number of bacterial infections. This includes use as an eye ointment to treat conjunctivitis. By mouth or by injection into a vein, it is used to treat meningitis, plague, cholera, a ...

provides an alternative in beta-lactam-intolerant patients. However, it is most important to treat the wound.

Animals

''P. multocida'' causes numerous pathological conditions in domestic animals. It often acts with other infectious agents, such as '' Chlamydia'' and ''

Mycoplasma ''Mycoplasma'' is a genus of bacteria that, like the other members of the class ''Mollicutes'', lack a cell wall around their cell membranes. Peptidoglycan (murein) is absent. This characteristic makes them naturally resistant to antibiotics ...

'' species and viruses. Environmental conditions (transportation, housing deficiency, and bad weather) also play a role. These diseases are considered caused by ''P. multocida'', alone or associated with other pathogens: *

Shipping fever Bovine respiratory disease (BRD) is the most common and costly disease affecting beef cattle in the world. It is a complex, bacterial or viral infection that causes pneumonia in calves which can be fatal. The infection is usually a sum of three c ...

in cattle and sheep ("shipping fever" may also be caused by ''Mannheimia haemolytica'', in the absence of ''P. multocida'', and ''M. haemolytica'' serovar A1 is known as the most common cause of the disease. The pathologic condition commonly arises where the causative organism becomes established by secondary infection, following a primary bacterial or viral infection, which may occur after stress, e.g. from handling or transport.) * Enzootic pneumonia of sheep (and goats, with frequent intervention of ''M. haemolytica'') * Fowl cholera ( chicken and other domestic poultry and cage birds) * Enzootic pneumonia and atrophic rhinitis of pigs * Pasteurellosis of

chinchilla Chinchillas are either of two species (''Chinchilla chinchilla'' and ''Chinchilla lanigera'') of crepuscular rodents of the parvorder Caviomorpha. They are slightly larger and more robust than ground squirrels, and are native to the Andes mount ...

s * Pasteurellosis of

rabbit Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit speci ...

s * Pasteurellosis is suspected to be the cause of recurrent mass mortality of Saiga antelopes.Saigas on the brink: Multidisciplinary analysis of the factors influencing mass mortality events. Richard A. Kock,, Mukhit Orynbayev, Sarah Robinson, Steffen Zuther, Navinder J. Singh, Wendy Beauvais, Eric R. Morgan, Aslan Kerimbayev, Sergei Khomenko, Henny M. Martineau, Rashida Rystaeva, Zamira Omarova, Sara Wolfs, Florent Hawotte, Julien Radoux and Eleanor J. Milner-Gulland. Science Advances 17 Jan 2018: Vol. 4, no. 1, eaao2314 DOI: 10.1126/sciadv.aao2314

References

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