Strep throat is contagious from the time a person is infected until they have been on antibiotics for at least 24 to 48 hours. Specifically:
- Without antibiotic treatment, a person with strep throat can remain contagious for about 2 to 3 weeks (14 to 21 days), even after symptoms improve
- Once antibiotic treatment begins, the contagious period shortens significantly, and people typically stop being contagious after 24 to 48 hours of antibiotics
- The incubation period-the time between exposure and symptom onset-is usually 2 to 5 days, during which an infected person can also spread the bacteria
In summary, strep throat is highly contagious until at least 24 to 48 hours after starting antibiotics, but without treatment, it can spread for several weeks. Good hygiene practices like handwashing and covering coughs help reduce transmission
