Diphtheria is a life-threatening bacterial infection that requires immediate care.
Certain bacteria cause diphtheria. The infection spreads between people through contact. This can happen by:
Your risk is higher if you:
People without symptoms can spread diphtheria to others. Symptoms usually appear within 2-5 days after infection.
The clearest sign of infection is a gray covering on the back of your throat. This covering can come off and block your airway.
Other common symptoms:
Left untreated, the bacteria can produce a poison that spreads throughout your body. This may cause heart, nerve, and kidney damage.
Your doctor will ask about your symptoms and health history. Your doctor may suspect diphtheria based on your symptoms and a physical exam. A test swab from your throat can confirm it.
Diphtheria is a medical emergency. Care will start right away, even if your test results aren’t ready.
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
Caring for Kids—Canadian Paediatric Society
Public Health Agency of Canada
Diphtheria. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/vaccines/pubs/pinkbook/dip.html. Updated November 9, 2015. Accessed May 14, 2018.
Diphtheria. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T114762/Diphtheria. Updated January 4, 2018. Accessed May 14, 2018.
Immunization schedules. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/vaccines/schedules/index.html. Updated February 6, 2018. Accessed May 22, 2017.
Td (tetanus, diphtheria) VIS. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/vaccines/hcp/vis/vis-statements/td.html. Updated April 11, 2017. Accessed May 14, 2018.
Tdap (tetanus, diphtheria, pertussis) VIS. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/vaccines/hcp/vis/vis-statements/tdap.html. Updated October 18, 2016. Accessed May 14, 2018.
Last reviewed May 2018 by David L. Horn, MD, FACP Last Updated: 5/14/2018