Is Strep throat Contagious?

Contagion summary:

Droplet infection, sneezes, coughes. Rarely contaminated food.

Contagiousness properties for Strep throat:

  Contagious by droplet?: Yes

  Contagious from food?: Yes, rarely.

Contagion summary:

The illness is spread by direct, close contact with patients via respiratory droplets (coughing or sneezing). Casual contact rarely results in transmission. Rarely, contaminated food, especially milk and milk products, can result in outbreaks. Untreated patients are most infectious for 2-3 weeks after onset of infection. Incubation period, the period after exposure and before symptoms show up, is 2-4 days. Patient is no longer infectious within 24 hrs. after treatment begins. (Source: excerpt from Group A Streptococcal Infections, NIAID Fact Sheet: NIAID)

Discussion about Contagion of Strep throat:

Some common diseases are occasionally foodborne, even though they are usually transmitted by other routes.  These include infections caused by Shigella , hepatitis A, and the parasites Giardia lamblia and Cryptosporidia.  Even strep throats have been transmitted occasionally through food.  (Source: excerpt from Foodborne Infections General: DBMD)

About contagion and contagiousness:

Contagion and contagiousness refers to how easily the spread of Strep throat is possible from one person to another. Other words for contagion include "infection", "infectiousness", "transmission" or "transmissability". Contagiousness has nothing to do with genetics or inheriting diseases from parents. For an overview of contagion, see Introduction to Contagion.