Symptoms of serious throat diseases include fever; an extremely painful sore throat that makes it difficult to swallow; tender, swollen lymph nodes; and tonsils that are inflamed and streaked with pus, says Mayo Clinic. These are symptoms of strep throat. Sore throat, hoarseness, fever and a gray membrane over the throat and tonsils are symptoms of diphtheria.
Pharyngoconjunctival fever has symptoms of severe sore throat, fever, swollen lymph nodes and runny nose, according to About.com. The eyes also burn, itch and tear. Fever can come on suddenly, rise as high as 104 degrees Fahrenheit and last for 10 days. Pharyngoconjunctival fever is fairly common among school children and is caused by the adenovirus.
Strep throat is caused by the Streptococcus pyogenes virus, says Mayo Clinic. Other symptoms are red spots on the back of the roof of the mouth, a rash, headache, fatigue and vomiting. Vomiting is especially prevalent in young children. Since these discomforts can be symptoms of other diseases, it is important to see a physician to make a diagnosis of strep throat and have it treated appropriately.
Diphtheria is also spread by bacteria, states Mayo Clinic. It is a potentially serious disease that requires medical care if there are symptoms. It is especially dangerous for young children. The gray membrane over the throat can interfere with the patient's breathing.