Strep throat is contagious from the time a person is infected until they have been on antibiotics for about 24 to 48 hours. Without antibiotic treatment, a person with strep throat can remain contagious for two to three weeks, even after symptoms improve
. Key points on contagiousness:
- With antibiotics: People become significantly less contagious within 24 to 48 hours after starting antibiotic treatment. After this period, they are generally no longer contagious and can return to work, school, or other activities
- Without antibiotics: The contagious period can last 2 to 3 weeks, during which the person can spread the infection to others through respiratory droplets (coughing, sneezing, talking) or direct contact with contaminated surfaces or objects
- Incubation period: It usually takes 2 to 5 days after exposure to develop symptoms, and people can be contagious during this time, even before symptoms appear
To prevent spreading strep throat, it is recommended to start antibiotics promptly if diagnosed, stay home from school or work until at least 24 hours after starting antibiotics, cover coughs and sneezes, wash hands frequently, and avoid sharing utensils or cups with others
. In summary, you are contagious with strep throat from shortly after infection until about 24 to 48 hours after starting antibiotics, or up to 2 to 3 weeks if untreated.
