Is Strep Throat Contagious

Before we talk about the incubation period for a strep throat infection, it is important to define the term “incubation period”.  An incubation period refers to the period during which the person is infected with a disease but is asymptomatic – or the infection is still not active. The incubation period for a strep throat differs from person to person, but it is usually for about 2-5 days. The average incubation period for a strep throat is 3 days. This simply means that the symptoms of a strep throat will only appear about 2-5 days after a person has been infected. At times adults do not show any symptoms and therefore do not take any medication. In such cases, they could succumb to an active infection within a three week period.

Now that we know about the incubation period for a strep throat, let us look at the contagious period of a strep throat. The contagious period for a strep throat is up to the time medication (antibiotics) are started. The contagious period is over once the person has been on antibiotics for 24 hours. It is important however, to finish the course of antibiotics that are prescribed, in order for the infection to be treated properly. Failure to do so will result in further complications such as kidney disease or rheumatic disease.

Frequently asked questions
  1. Antibiotic Treatment of Children With Sore Throat; Jeffrey A. Linder, David W. Bates, Grace M. Lee, Jonathan A. Finkelstein, JAMA. 2005;294(18):2315-2322.doi:10.1001/jama.294.18.2315
  2. Center for Disease Control; July 17, 2005. Statement on GAS Disease.
  3. Hayes, C. and H. Williamson. July 17, 2005. Management of Group A Beta-Hemolytic Streptococcal Pharyngitis.