Gram Positive: S. pneumoniae, viridans group Streptococci, S. anginosus group, beta-hemolytic Streptococci (Group A/B/C/G streptococci), E. faecalis.
Gram Negative: N. meningitidis, Pasteurella multocida
Anaerobes: Peptostreptococci, Actinomyces, Clostridia (non-difficile), P. acnes, Fusobacterium, Prevotella.
Others: T. pallidum, Leptospira