<prompt> Causative agent of sore throat is: September 2005Staphylococcus aureusStreptococcus pyogenesH. InfluenzaeCorynebacterium diphtheriae  <response>: Ans. B: Streptococcus pyogenes The primary site of invasion of human body by streptococcus pyogenes is the throat. Primary bacterial pathogens that account for approximately 30 of cases of pharyngitis include Streptococcus pyogenes Group A Beta Hemolytic Streptococci common, group C streptococci uncommon, group G streptococci uncommon, Neisseria gonorrhoeae uncommon, Corynebacterium diphtheriae rare, and Corynebacterium hemolyticum extremely rare. Viruses are isolated in approximately 40 of cases and include rhinovirus, adenovirus, parainfluenza virus, coxsackievirus, coronavirus, echovirus, herpes simplex virus, Epstein-Barr virus mononucleosis, and cytomegalovirus. Other probable copathogens for pharyngitis in children include Staphylococcus aureus, Haemophilus influenzae, Branhamella catarrhalis, Bacteroides fragilis, Bacteroides oralis, Bacteroides melaninogenicus, Fusobacterium species, and Peptostreptococcus species. 