Most cases are due to an infectious organism acquired from close contact with an infected individual. Viral Exudative<unk>  in a person with infectious mononucleosis These comprise about 40–80% of all infectious cases and can be a feature of many different types of viral infections. ::::::::::*Adenovirus is the most common of the viral causes. Typically, the degree of neck lymph node enlargement is modest and the throat often does not appear red, although it is painful. ::::::::::*The family Orthomyxoviridae which cause influenza are present with rapid onset high temperature, headache, and generalized ache. A sore throat may be associated. ::::::::::*Infectious mononucleosis ("glandular fever") is caused by the Epstein–Barr virus. This may cause significant lymph-node swelling and an exudative tonsillitis with marked redness and swelling of the throat. The heterophile test can be used if this is suspected. ::::::::::*Herpes simplex virus can cause multiple mouth ulcers. ::::::::::*Measles ::::::::::*Common cold: rhinovirus, coronavirus, respiratory syncytial virus, and parainfluenza virus can cause infection of the throat, ear, and lungs causing standard cold-like symptoms and often pain. Bacterial A number of different bacteria can infect the human throat. The most common is group A streptococcus (Streptococcus pyogenes), but others include Streptococcus pneumoniae, Haemophilus influenzae, Bordetella pertussis, Bacillus anthracis, Corynebacterium diphtheriae, Neisseria gonorrhoeae, Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Fusobacterium necrophorum. ;;Streptococcal<unk>  A case of strep throat Streptococcal<unk>  or strep throat is caused by a group A beta-hemolytic streptococcus (GAS). It is the most common bacterial cause of cases of<unk>  (15–30%). Common symptoms include fever, sore throat, and large lymph nodes. It is a contagious infection, spread by close contact with an infected individual. A definitive diagnosis is made based on the results of a throat culture. Antibiotics are useful to both prevent complications (such as rheumatic fever) and speed recovery. ;;Fusobacterium necrophorum Fusobacterium necrophorum is a normal inhabitant of the oropharyngeal flora and can occasionally create a peritonsillar abscess. In one out of 400 untreated cases, Lemierre's syndrome occurs. ;;Diphtheria Diphtheria is a potentially life-threatening upper respiratory infection caused by Corynebacterium diphtheriae, which has been largely eradicated in developed nations since the introduction of childhood vaccination programs, but is still reported in the Third World and increasingly in some areas in Eastern Europe. Antibiotics are effective in the early stages, but recovery is generally slow. ;;Others A few other causes are rare, but possibly fatal, and include parapharyngeal space infections: peritonsillar abscess ("quinsy abscess"), submandibular space infection (Ludwig's angina), and epiglottitis. Fungal Some cases of<unk>  are caused by fungal infection, such as Candida albicans, causing oral thrush. Noninfectious<unk>  may also be caused by mechanical, chemical, or thermal irritation, for example cold air or acid reflux. Some medications may produce<unk> , such as pramipexole and antipsychotics.
Pharyngitis
Epiglottitis
Laryngitis
Retropharyngeal abscess
Sinusitis
Thyroiditis
Tonsillitis
Streptococcal pharyngitis