Title: Pasteurella multocida

{{Short description|Species of bacterium}}
{{Speciesbox
| image = PHIL 3621.tif
| image_alt = Gram-stained photomicrograph depicting numerous &quot;Pasteurella multocida&quot; bacteria
| image_caption = [[Gram-stain]]ed photomicrograph depicting numerous ''Pasteurella multocida'' bacteria
| genus = Pasteurella
| species = multocida
| authority = Trevisan 1887 (Approved Lists 1980)
}}

'''''Pasteurella multocida''''' is a [[Gram-negative]], nonmotile, [[penicillin]]-sensitive [[coccobacillus]] from the family [[Pasteurellaceae]].&lt;ref name= KuhnertChristensen&gt;{{cite book | editor = Kuhnert P | editor2 = Christensen H | title = Pasteurellaceae: Biology, Genomics and Molecular Aspects | publisher = Caister Academic Press | year = 2008 | url=http://www.horizonpress.com/past |  isbn =978-1-904455-34-9 }}&lt;/ref&gt; Strains of the species are currently classified into five [[serogroup]]s (A, B, D, E, F) based on [[Bacterial capsule|capsular]] composition and 16 somatic [[serovar]]s (1–16). ''P. multocida'' is the cause of a range of diseases in mammals and birds, including [[fowl cholera]] in [[poultry]], [[atrophic rhinitis]] in pigs, and bovine hemorrhagic [[septicemia]] in cattle and buffalo. It can also cause a [[zoonotic]] infection in humans, which typically is a result of bites or scratches from domestic pets. Many mammals (including domestic cats and dogs) and birds harbor it as part of their normal respiratory [[microbiota]].

==History==
''Pasteurella multocida'' was first found in 1878 in cholera-infected birds.  However, it was not isolated until 1880, by [[Louis Pasteur]], in whose honor ''[[Pasteurella]]'' is named.&lt;ref&gt;{{cite web|last=Pasteur|first=Louis|url=http://www.pasteurbrewing.com/the-attenuation-of-the-causal-agent-of-fowl-cholera/|title=The Attenuation of the Causal Agent of Fowl Cholera|date=2011-05-13}}&lt;/ref&gt;

== Disease ==
:''See: [[Pasteurellosis]]''
''Pasteurella multocida'' causes a range of diseases in wild and domesticated animals, as well as humans.  The bacterium is found in birds, [[Feline zoonosis|cats]], dogs, rabbits, cattle, and pigs.  In birds, ''P. multocida'' causes avian or [[fowl cholera]] disease; a significant disease present in commercial and domestic poultry flocks worldwide, particularly layer flocks and parent breeder flocks. ''P. multocida'' strains that cause fowl cholera in poultry typically belong to the serovars 1, 3, and 4.  In the wild, fowl cholera has been shown to follow bird migration routes, especially of [[snow goose|snow geese]]. The ''P. multocida'' serotype-1 is most associated with avian cholera in North America, but the bacterium does not linger in [[wetland]]s for extended periods of time.&lt;ref&gt;Blanchlong, JA. &quot;Persistence of pasteurella multocida in wetlands following avian cholera outbreaks.&quot; Journal of Wildlife diseases, 2006; 42(1):33-39&lt;/ref&gt;   ''P. multocida'' causes atrophic rhinitis in pigs;&lt;ref&gt;Eliás B, Hámori D. Data on the aetiology of swine atrophic rhinitis. V. The role of genetic factors. Acta Vet Acad Sci Hung. 1976;26(1):13–19. [PubMed]&lt;/ref&gt; it also can cause [[pneumonia]] or [[bovine respiratory disease]] in cattle.&lt;ref&gt;Irsik, M B Bovine respiratory disease associated with Mannheimia Haemolytica or pastuerella multocida.  VM 163, University of Florida&lt;/ref&gt;&lt;ref name=&quot;KokotovicFriis2007&quot;&gt;{{cite journal|last1=Kokotovic|first1=Branko|last2=Friis|first2=Niels F|last3=Ahrens|first3=Peter|journal=Acta Veterinaria Scandinavica |title = Mycoplasma alkalescens demonstrated in bronchoalveolar lavage of cattle in Denmark |volume=49|issue=1|year=2007|pages=2|issn=1751-0147|doi=10.1186/1751-0147-49-2|pmid=17204146|pmc=1766361 |doi-access=free }}&lt;/ref&gt; It may be responsible for mass mortality in [[saiga antelope]]s.&lt;ref&gt;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: [https://www.science.org/doi/10.1126/sciadv.aao2314 Saigas on the brink: Multidisciplinary analysis of the factors influencing mass mortality events]. Science Advances  17 Jan 2018: Vol. 4, no. 1, eaao2314 [[DOI: 10.1126/sciadv.aao2314]]&lt;/ref&gt;

In humans, ''P. multocida'' is the most common cause of wound infections after dog or cat bites. The infection usually shows as soft tissue inflammation within 24 hours. High [[leukocyte]] and [[neutrophil]] counts are typically observed, leading to an inflammatory reaction at the infection site (generally a diffuse, localized [[cellulitis]]).&lt;ref name=&quot;Sherris&quot;&gt;{{cite book | editor = Ryan KJ | editor2 = Ray CG | title = Sherris Medical Microbiology | edition = 4th | publisher = McGraw Hill | year = 2004 | isbn = 0-8385-8529-9 }}&lt;/ref&gt;  It can also infect other locales, such as the respiratory tract, and is known to cause regional [[lymphadenopathy]] (swelling of the lymph nodes). In more serious cases, a [[bacteremia]] can result, causing an [[osteomyelitis]] or [[endocarditis]]. Patients with a joint replacement (perhaps notably knee replacement) in place may, in particular, be at risk of secondary infection of that joint during an episode of P multocida cellulitis/bacteraemia. The bacteria may also cross the [[blood–brain barrier]] and cause [[meningitis]].&lt;ref name=&quot;ReferenceA&quot;&gt;Casolari C, Fabio U.  Isolation of Pasteurella multocida from Human Clinical Specimens: First Report in Italy.  European Journal of Epidemiology.  Sept 1988; 4(3):389-90&lt;/ref&gt;

==Virulence, culturing, and metabolism==
''Pasteurella. multocida'' expresses a range of [[virulence factor]]s including a [[polysaccharide]] [[Bacterial capsule|capsule]] and the variable [[carbohydrate]] surface molecule, [[lipopolysaccharide]] (LPS). The capsule has been shown in strains of serogroups A and B to help resist [[phagocytosis]] by host [[immune cell]]s and capsule type A has also been shown to help resist complement-mediated [[lysis]].&lt;ref&gt;Chung JY, Wilkie I, Boyce JD, Townsend KM, Frost AJ, Ghoddusi M, Adler B: Role of capsule in the pathogenesis of fowl cholera caused by Pasteurella multocida serogroup A. Infect Immun 2001, 69(4):2487-2492.&lt;/ref&gt;&lt;ref&gt;Boyce JD, Adler B: The capsule is a virulence determinant in the pathogenesis of Pasteurella multocida M1404 (B:2). Infect Immun 2000, 68(6):3463-3468.&lt;/ref&gt; The LPS produced by ''P. multocida'' consists of a hydrophobic lipid A molecule (that anchors the LPS to the outer membrane), an inner core, and an outer core, both consisting of a series of sugars linked in a specific way. There is no [[O-antigen]] on the LPS and the molecule is similar to LPS produced by ''[[Haemophilus influenzae]]'' and the [[lipooligosaccharide]] of ''[[Neisseria meningitidis]]''. A study in a serovar 1 strain showed that a full-length LPS molecule was essential for the bacteria to be fully virulent in chickens.&lt;ref&gt;Harper M, Cox AD, St Michael F, Wilkie IW, Boyce JD, Adler B. A heptosyltransferase mutant of ''Pasteurella multocida'' produces a truncated [[lipopolysaccharide]] structure and is attenuated in virulence. Infect. Immun. 2004; 72(6):3436-43.&lt;/ref&gt; Strains that cause atrophic rhinitis in pigs are unique as they also have ''P. multocida'' toxin (PMT) residing on a [[bacteriophage]]. PMT is responsible for the twisted snouts observed in pigs infected with the bacteria. This toxin activates [[Rho family of GTPases|Rho]] [[GTPase]]s, which bind and hydrolyze [[Guanosine triphosphate|GTP]], and are important in [[actin]] stress fiber formation. Formation of stress fibers may aid in the [[endocytosis]] of ''P. multocida''. The host cell cycle is also modulated by the toxin, which can act as an intracellular [[mitogen]].&lt;ref&gt;Lacerda HM, Lax AJ, Rozenqurt E. Pasteurella multocida toxin, a potent intracellularly acting mitogen, induces p125FAK and paxillin tyrosine phosphorylation, actin stress fiber formation, and focal contact assembly in Swiss 3T3 cells. J Biol Chem. 5 Jan 1996; 271(1):439-45.&lt;/ref&gt; ''P. multocida'' has been observed invading and replicating inside host [[amoeba]]e, causing lysis in the host. ''P. multocida'' will grow at {{Convert|37|C||abbr=}} on [[blood agar|blood]] or [[chocolate agar]], [[High strength agar|HS agar]],&lt;ref&gt;[https://www.younginfrontier.com/@/hs-agar], by Younginfrontier, [https://www.younginfrontier.com/web/content/162038?unique=cf984919c2c9473df168ca0ab7e50de8ade7b6e9&amp;download=true]. [https://www.condalab.com/products/search/?tx_condalabproducts_busqueda%5BproductoCod%5D=1809&amp;tx_condalabproducts_busqueda%5Bcat1%5D=&amp;tx_condalabproducts_busqueda%5Bcat2%5D=&amp;tx_condalabproducts_busqueda%5Bcat3%5D=&amp;tx_condalabproducts_busqueda%5Baction%5D=show&amp;tx_condalabproducts_busqueda%5Bcontroller%5D=Categoria&amp;cHash=1a2f2c758b5ba27747b0b6ab0ac3cc45 HS agar], by Laboratorios CONDA, [https://www.condalab.com/pdf/1809.pdf PDF].&lt;/ref&gt; but will not grow on [[MacConkey agar]]. Colony growth is accompanied by a characteristic &quot;mousy&quot; odor due to [[metabolism|metabolic]] products.

A [[facultative anaerobe]], ''P. multocida'' it is [[Oxidase test|oxidase-positive]] and [[Catalase|catalase-positive]]. It can also [[fermentation (biochemistry)|ferment]] a large number of [[carbohydrate]]s in anaerobic conditions.&lt;ref name=&quot;ReferenceA&quot; /&gt; The survival of ''P. multocida'' bacteria has also been shown to be increased by the addition of salt into their environments. Levels of [[sucrose]] and [[pH]] also have been shown to have minor effects on bacterial survival.&lt;ref&gt;Bredy, JP. &quot;The effects of six environmental variables on Pasteurella multocida populations in water.&quot; Journal of Wildlife Diseases, vol. 25, no. 2 (232–239)&lt;/ref&gt;

==Diagnosis and treatment==
Diagnosis of the bacterium in humans was traditionally based on clinical findings, and culture and [[serology|serological]] testing, but [[false negatives]] have been a problem due to easy death of ''P. multocida'', and serology cannot differentiate between current infection and previous exposure.  The quickest and most accurate method for confirming an active ''P. multocida'' infection is molecular detection using [[polymerase chain reaction]].&lt;ref&gt;Miflin, J.K. and Balckall, P.J. (2001) Development of a 23 SrRNA-based PCR assay for the identification of Pasteurella multocida. Lett. Appl. Microbiol. 33: 216–221&lt;/ref&gt;

This bacterium can be effectively treated with [[β-lactam antibiotic]]s, which inhibit cell wall synthesis.  It can also be treated with [[fluoroquinolones]] or [[tetracyclines]]; fluoroquinolones inhibit bacterial [[DNA synthesis]] and tetracyclines interfere with [[peptide synthesis|protein synthesis]] by binding to the bacterial [[30S]] [[ribosome|ribosomal]] subunit. Despite poor ''in vitro'' susceptibility results, [[macrolide]]s (binding to the ribosome) also can be applied, certainly in the case of pulmonary complications. Due to the polymicrobial etiology of ''P. multocida'' infections, treatment requires the use of antimicrobials targeted at the elimination of both aerobic and anaerobic, Gram-negative bacteria. As a result, [[Amoxicillin/clavulanic acid|amoxicillin-clavulanate]] (a beta-lactamase inhibitor/penicillin combination) is seen as the treatment of choice.&lt;ref&gt;''Red Book: 2006 Report of the Committee on Infectious Diseases - 27th Ed.''&lt;/ref&gt;

==Current research==
''Pasteurella multocida'' [[mutant]]s are being researched for their ability to cause diseases.  ''In vitro'' experiments show the bacteria respond to low iron.  Vaccination against progressive atrophic rhinitis was developed by using a recombinant derivative of ''P. multocida'' toxin. The vaccination was tested on pregnant gilts (female swine without previous litters). The piglets born to treated gilts were inoculated, while the piglets born to unvaccinated mothers developed atrophic rhinitis.&lt;ref&gt;Nielsen JP Vaccination against progressive atrophic rhinitis with a recombinant &quot;Pasteurella multocida&quot; toxin derivative. Canadian Journal of Veterinary Research, vol.55, no.2 (128–138)&lt;/ref&gt;
Other research is being done on the effects of protein, pH, temperature, sodium chloride (NaCl), and sucrose on  ''P. multocida'' development and survival in water.  The research seems to show the bacteria survive better in {{convert|18|C|F}} water compared to {{convert|2|C|F}} water. The addition of 0.5% NaCl also aided bacterial survival, while the sucrose and pH levels had minor effects, as well.&lt;ref&gt;Bredy, JP. The effects of six environmental variables on ''P. multocida'' populations in water. &quot;Journal of Wildlife Diseases&quot;, vol. 25, no.2 (232–239)&lt;/ref&gt;  Research has also been done on the response of ''P. multocida'' to the host environment. These tests use DNA microarrays and proteomics techniques. ''P. multocida''-directed mutants have been tested for their ability to produce disease.  Findings seem to indicate the bacteria occupy host niches that force them to change their gene expression for energy metabolism, uptake of iron, amino acids, and other nutrients. ''In vitro'' experiments show the responses of the bacteria to low iron and different iron sources, such as [[Transferrin|transferrin&lt;!--NOT transferring--&gt;]] and [[hemoglobin]]. ''P. multocida'' genes that are upregulated in times of infection are usually involved in nutrient uptake and metabolism.  This shows true virulence genes may only be expressed during the early stages of infection.&lt;ref&gt;Boyce, JD.  How does ''P. multocida'' respond to the host environment? &quot;Current Opinion in Microbiology&quot; vol.9 no.1 (117–122)&lt;/ref&gt;

[[Transformation (genetics)|Genetic transformation]] is the process by which a recipient bacterial cell takes up DNA from a neighboring cell and integrates this DNA into the recipient's [[genome]].  ''P. multocida'' DNA contains high frequencies of putative [[Uptake signal sequence|DNA uptake sequence]]s (DUSs) identical to those in ''Hemophilus influenzae'' that promote donor DNA uptake during [[Transformation (genetics)|transformation]].&lt;ref name=Davidsen&gt;{{cite journal |vauthors=Davidsen T, Rødland EA, Lagesen K, Seeberg E, Rognes T, Tønjum T |title=Biased distribution of DNA uptake sequences towards genome maintenance genes |journal=Nucleic Acids Res. |volume=32 |issue=3 |pages=1050–8 |year=2004 |pmid=14960717 |pmc=373393 |doi=10.1093/nar/gkh255 }}&lt;/ref&gt;  The location of these sequences in ''P. multocida'' shows a skewed distribution towards genome maintenance genes, such as those involved in [[DNA repair]]. This finding suggests that ''P. multocida'' might be competent to undergo transformation under certain conditions, and that genome maintenance genes involved in transforming donor DNA may preferentially replace their damaged counterparts in the DNA of the recipient cell.&lt;ref name=Davidsen /&gt;

==References==
{{Reflist|30em}}

==External links==
* [https://web.archive.org/web/20070226145037/http://www.healthatoz.com/healthatoz/Atoz/common/standard/transform.jsp?requestURI=%2Fhealthatoz%2FAtoz%2Fency%2Fanimal_bite_infections.jsp Animal bite infections (healthAtoZ.com)]
* [https://gold.jgi.doe.gov/organisms?setColumns=yes&amp;Organism.Organism+Name=multocida&amp;Organism.Domain= Genome Projects] from [[Genomes OnLine Database]]
* [https://bacdive.dsmz.de/strain/11729 Type strain of ''Pasteurella multocida'' at Bac''Dive'' -  the Bacterial Diversity Metadatabase]
* [https://www.telegraph.co.uk/news/2025/07/23/woman-died-dog-licked-wound/ Woman died from dog lick] 23 July 2025 ''[[The Daily Telegraph]]''

{{Taxonbar|from=Q310656}}

[[Category:Bacterial diseases]]
[[Category:Zoonoses]]
[[Category:Pasteurellales]]
[[Category:Cat diseases]]
[[Category:Bacteria described in 1887]]