Gram-negative, nonmotile, penicillin-sensitive coccobacillus belonging to the Pasteurellaceae family.
Strains belonging to the species are currently classified into 5 serogroups (A, B, D, E, F) based on capsular composition and 16 somatic serovars.
Pasteurella multocida is the cause of a range of diseases in mammals and birds. It can also cause a zoonotic infection in humans, which typically is a result of bites or scratches from domestic pets. Many mammals and birds harbor it as part of their normal respiratory microbiota including domestic cats.
P. multocida expresses a range of virulence factors including a polysaccharide capsule and the variable carbohydrate surface molecule, lipopolysaccharide (LPS). The capsule has been shown in strains belonging to serogroups A and B to help resist phagocytosis by host immune cells and capsule type A has also been shown to help resist complement-mediated lysis.
Important considerations: The choice of an agent should be based on local antimicrobial sensitivities, site of infection, cost, and comorbid conditions. Generally, the most common agents/regimens are listed first. Listed dosages may need to be adjusted for renal dysfunction. Therapy is usually continued for 7 to 10 days.
Amoxicillin 500 mg orally three times daily or 875mg bid.