What causes strep throat?

Strep throat is specifically caused by an infection with Streptococcal bacteria, most commonly Streptococcus pyogenes, which is also known as Group A Streptococcus. This type of bacteria can lead to inflammation of the throat and tonsils, resulting in the characteristic symptoms of strep throat, including a sore throat, fever, and swollen lymph nodes. The bacterial origin of the disease is critical to its diagnosis and treatment, as it requires antibiotic therapy to eradicate the bacteria and prevent potential complications, such as rheumatic fever.

In contrast, viral infections, allergic reactions, and fungal infections typically do not cause strep throat; they may lead to similar symptoms but are fundamentally different in their etiology and management.