Written and reviewed by Emily W., PhD · Last reviewed: December 31, 2025
Most adult sore throats are viral. Estimates put strep at roughly 5 to 15% of adult cases. Since strep is the main reason to prescribe antibiotics for a sore throat, telling them apart is the whole question.
The single most useful clue
A cough points strongly to viral. Strep bacteria infect the throat and tonsils, not the lower airways, so cough is unusual with strep. If you have a sore throat plus a cough, runny nose, and hoarseness, the odds heavily favour a virus.
Side by side
| Strep throat | Viral sore throat | |
|---|---|---|
| Onset | Sudden | Gradual |
| Cough | Usually absent | Common |
| Runny nose | Usually absent | Common |
| Fever | Common, often above 101°F | Mild or absent |
| White patches on tonsils | Common | Possible but less typical |
| Neck glands | Swollen and tender at the front | Mildly swollen |
| Pain on swallowing | Severe | Mild to moderate |
| Hoarseness | Uncommon | Common |
| Roof of mouth | Tiny red spots possible | Not typical |
The four-point score clinicians use
A widely used tool called the Centor score gives one point for each of:
- Fever in the current illness
- Absence of cough
- Swollen, tender lymph nodes at the front of the neck
- White coating or exudate on the tonsils
Score 0 or 1 makes strep unlikely and testing is generally unnecessary. Score 2 or 3 warrants a rapid test. Score 4 makes strep considerably more likely and testing is recommended.
Note that even a score of 4 does not confirm strep. This is a guide for who to test, not a substitute for testing.
Why testing matters
A rapid strep test takes minutes and is widely available at urgent care and many pharmacies. If negative in an adult, no antibiotic is needed. If positive, treatment prevents rheumatic fever — a rare but serious complication where the immune response damages heart valves two to four weeks after the throat infection.
That complication is the entire reason strep gets antibiotics. The sore throat itself would resolve without them in about a week.
What causes viral sore throats
Rhinovirus, influenza, COVID, adenovirus, and Epstein-Barr virus (mononucleosis) among others. COVID in particular has become a very common cause of severe sore throat — see the four-way comparison.
Consider mononucleosis if you are under 30 and have a sore throat lasting more than a week with extreme fatigue and swollen glands on both sides of the neck.
If you have no fever at all
Strep without fever is possible but less likely. Other explanations move up the list, including acid reflux, allergies, and dry air. See sore throat but no fever.
Treating either one
For pain: ibuprofen generally works better than acetaminophen here because inflammation is central. Salt water gargle, cold foods, warm tea with honey, and soft foods all help. See the pain relief comparison.
If strep is confirmed, finish the full ten-day antibiotic course even after you feel better — see how long you are contagious after starting antibiotics.
Get urgent care for
Difficulty breathing or swallowing, drooling, inability to open the mouth fully, severe swelling on one side, a muffled or “hot potato” voice, or a rash with a sandpaper texture. These suggest complications needing same-day assessment.
Related reading
- Flu vs COVID vs RSV vs Cold: Symptom Comparison Chart
- Sore Throat but No Fever: What It Actually Means
- Acetaminophen vs Ibuprofen for Fever: Which Works Better?
Sources
- Centers for Disease Control and Prevention
- MedlinePlus — U.S. National Library of Medicine
- Drug Information — MedlinePlus
Medical disclaimer: This article is for general information only and is not a substitute for advice from a qualified healthcare professional. It should not be used to diagnose or treat a health problem. Always speak to your doctor or pharmacist about your own situation. If you think you may have a medical emergency, call 911 or go to your nearest emergency department.
