Does pharyngitis cause death?

Normal throat infection will normally not be fatal, but there are a few causes of respiratory tract infection that are rare, but possibly fatal, including parapharyngeal space infections: peritonsillar abscess ("quinsy"), submandibular space infection (Ludwig's angina), and epiglottitis. Diphtheria is a potentially life-threatening upper respiratory infection caused by Corynebacterium diphtheriae.
You probably just have an ordinary sore throat or strep throat, I suggest you go to a doctor, you might need antibiotics to clear it up.