Quick Answer
YES. Strep throat is highly contagious.
Good News: You stop being contagious 24 hours after starting antibiotics, provided your fever is gone.
Bad News: Without treatment, you can remain contagious for 2 to 3 weeks even if you feel better.
How It Spreads
- • Respiratory Droplets: Coughing or sneezing.
- • Direct Contact: Sharing utensils, water bottles, or kissing.
- • Surfaces: Touching a doorknob or phone with bacteria on it, then touching your mouth/nose.
Incubation Period
2 to 5 Days
It typically takes 2 to 5 days after exposure for you to start feeling sick. You can be contagious during this time before symptoms appear.
Strep vs. Sore Throat
| Symptom | Strep Throat | Viral Sore Throat |
|---|---|---|
| Fever | Sudden, often >101°F | Mild or none |
| Throat Appearance | Red, swollen tonsils, white patches/streaks | Red, swollen |
| Cough | Rarely has a cough | Often cough, runny nose |
| Pain Level | Severe, worse when swallowing | Moderate, scratchy |
Warning
Untreated strep throat can lead to serious complications like rheumatic fever (which damages the heart) or kidney inflammation. Always complete your full course of antibiotics, even if you feel better.
Medical Review
Reviewed by: Ricardo Hamilton, MD
Last Updated: December 15, 2025
Sources: CDC, Mayo Clinic