Peak in 5-15yr old
Rare in <2yr of age
Accounts for only 15-30% of<unk> 
Caused by S. pyogenes (Group A strep)
Peak season is late winter / early spring
Transmission is respiratory secretions
Incubation period is 24-72 hours
Antibiotics shorten symptoms by 16 hours
Streptococcal pharyngitis
Acute rheumatic fever
Croup
Scarlet fever
Pertussis
Suppurative complications
Rabies
Peritonsillar abscess