Skip to main content
King County logo

Diphtheria is an acute illness caused by the bacterium Corynebacterium diphtheriae. It is spread primarily by respiratory droplets (droplet spread) produced when an infected person coughs or sneezes, but it can also be spread by discharge from skin lesions or, rarely, through fomites (contaminated objects). Since universal vaccination against diphtheria began in the 1940s, diphtheria has been very uncommon in the United States; however, the disease still occurs in developing countries and countries of the former Soviet Union and presents a risk to susceptible travelers.

Resources for the general public

Resources for health care professionals

Purpose of surveillance:

  • To facilitate diagnosis of toxin-producing diphtheria infections
  • To facilitate appropriate treatment of cases, disease control measures, and preventive treatment for contacts of cases
  • To identify other exposed persons at risk for diphtheria

Local epidemiology:

No cases of toxigenic diphtheria have been reported in Washington state since 1981.