Streptococcus porcinus
Streptococcus porcinus is a species of Gram-positive bacterium in the genus Streptococcus. It was first described in 1966 following its isolation from pigs, where it was associated with a variety of suppurative infections. The species name refers to its porcine origin.
S. porcinus was originally isolated from pigs, but subsequent studies have detected it in a broad range of hosts, including cattle, sheep, goats, and occasionally humans. In animals, it has been isolated from abscesses, lymphadenitis, and genitourinary infections. In humans, it is a rare cause of disease but has been isolated from throat swabs, wound infections, and occasionally from invasive infections such as endometritis and neonatal sepsis.
Differentiation
S. porcinus is classified within the pyogenic streptococci and is most commonly associated with Lancefield group E antigens, though some strains may express group P or U antigens. It may be misidentified as Streptococcus agalactiae due to some overlapping phenotypic traits; however, molecular methods and full biochemical profiles allow for accurate identification.
In swine, S. porcinus has been associated with cervical abscesses, reproductive tract infections, and septicemia. In humans, infections are rare but may include pharyngitis, abscess formation, and postpartum infections. Its pathogenic potential in humans is still considered opportunistic.
Type strain
The type strain of S. porcinus is NCTC 10999.