Skip to main content

Is diphtheria contagious?

Page last updated 09 July 2018

Yes, diphtheria is highly contagious and is easily spread by coughing or sneezing. 

Without treatment, people with diphtheria are infectious for up to 4 weeks from the beginning of their symptoms. Some people can also become carriers and are infectious for longer.

Completing the immunisation schedule is important, as those who have not been fully immunised are at risk of developing the disease if they are exposed to the bacteria.

Sources & Citations

  1. Australian Government. Department of Health. Australia’s notifiable disease status, 2014: Annual report of the National Notifiable Diseases Surveillance System (main page). Available at (accessed 7 April 2018).
  2. Victorian Government. Better Health Channel. Diphtheria. Available at (accessed 7 April 2018).
  3. Centers for Disease Control. Diphtheria. Causes and Transmission. Available at (accessed 7 April 2018).

SPANZ.SAPAS.18.04.0134a - Date of preparation May 2018