Sore Throat: Viral vs. Bacterial - When to Get a Strep Test

Most sore throats are caused by viral infections and resolve without antibiotics. However, strep throat (caused by Group A Streptococcus) requires antibiotic treatment to prevent complications. Viral sore throat signs include gradual onset, accompanied by cold symptoms (runny nose, cough, sneezing), mild to moderate pain, low or no fever, and scratchy or irritated feeling. Strep throat signs include sudden onset, severe pain especially when swallowing, fever above 38°C, swollen and tender lymph nodes in the neck, white patches or pus on the tonsils, absence of cough (a key differentiator), and possible headache, nausea, or abdominal pain. When to get tested: the Centor criteria help guide clinical decision-making. If you have fever, tonsillar exudates (pus), tender anterior cervical lymph nodes, and absence of cough, strep testing is recommended. Untreated strep throat can lead to serious complications including rheumatic fever, peritonsillar abscess, and kidney inflammation. A rapid strep test or throat culture confirms the diagnosis. Treatment for strep throat is typically a 10-day course of penicillin or amoxicillin. A physician can assess your symptoms and order testing through telehealth followed by in-person swab collection. *This article is for informational purposes only.*

This article is for informational purposes only and does not constitute medical advice. Content reviewed by licensed Canadian physicians. Last updated February 2026.