In terms of pathophysiology, rhinovirus infection resembles the immune response. The viruses do not cause damage to the cells of the<unk><unk>  tract, but rather cause changes in the tight junctions of epithelial cells. This allows the virus to gain access to tissues under the epithelial cells and initiate the innate and adaptive immune responses. Up to 15% of acute pharyngitis cases may be caused by bacteria, most commonly Streptococcus pyogenes, a group A streptococcus in streptococcal pharyngitis ("strep throat"). Other bacterial causes are Streptococcus pneumoniae, Haemophilus influenzae, Corynebacterium diphtheriae, Bordetella pertussis, and Bacillus anthracis. Sexually transmitted infections have emerged as causes of oral and pharyngeal infections.
Upper respiratory tract infection
Carbon monoxide poisoning
Lower respiratory tract infection
Respiratory tract infection
Post-viral cough
Allergic rhinitis
Croup
Bronchorrhea