Table 1.

Causative agents found in upper respiratory infection (pharyngitis)

Viral
Rhinovirus	20%
Coronavirus	≥ 5%
Adenovirus	5%
Herpes simplex	4%
Parainfluenza and Influenza	4%
Coxsackie-A, EBV, CMV, HIV-1	< 1% each
Bacterial
Streptococcus pyogenes Group A	15–30%
Streptococcus pyogenes Group C	5–10%
Corynebacterium diphteriae	≥ 1%
Mycoplasma pneumoniae	< 1%
Chlamydia pneumoniae and Mycoplasma hominis	Unknown
Corynebacteria other than C. diphteriae,	<1% each
Neisseria gonorrhoeae, Yersinia enterocolitica,
Treponema pallidum, and agents causing mixed anaerobic infections (i.e., Plaut Vincent’s angina; peritonsillar abscess)

Data adapted from (4).