Diphtheria

Diphtheria  

What is it? 

Diphtheria is a communicable disease caused by the Corynebacterium diphtheriae and  Corynebacterium ulcerans bacteria, which can cause serious respiratory and skin infections. Prior to accessible and widespread vaccination for diphtheria, an estimated 1 million cases of diphtheria and 50,000 – 60,000 deaths occurred annually in low and middle income countries. Following the expanded and accessible diphtheria vaccination programs, reported cases decreased by over 90%. 

Symptoms of respiratory diphtheria include a fever, severe sore throat, malaise, runny nose, and a grey or black membrane coating on the tonsils and throat caused by bacterial produced toxins, which can lead to breathing and swallowing problems. Symptoms of skin diphtheria, known as cutaneous diphtheria, include ulcers and wounds that are sore, full of pus and may be surrounded by greyish skin patches. 

Symptoms can occur between 2-5 days after infection, and can last for four to six weeks in people who are untreated. 

How is it transmitted? 

Diphtheria is spread through the respiratory droplets of a carrier or infected person, via direct deposition of droplets or through contact transmission of a contaminated surface.   

At risk groups 

Diphtheria is considered to be rare in Australia, New Zealand and other high-income countries due to high rates of childhood vaccination, however it still exists in many countries where vaccines are not available or vaccination rates are low.  

People at risk of diphtheria include those who are unvaccinated, those who have not received booster vaccinations, and travellers to or from areas with known diphtheria cases including South East Asia, and Eastern Europe.  

Prevention 

Vaccination is the best way to prevent diphtheria infection. Diphtheria vaccination should be administered to children in a multi-dose schedule, as a booster to adolescents, and as a booster dose every ten-years for adults. 

Cases of diphtheria should be managed with preventative measures that include strict hand hygiene, respiratory etiquette, and the use of PPE consistent with standard and droplet precautions when in a healthcare facility. Regular cleaning with a detergent and disinfectant of contaminated and high-touch surfaces will prevent contact transmission.  

Key messages: 

• Diphtheria is a vaccine preventable disease, with booster vaccinations needed to maintain immunity.  
• Vaccination is free through the National Immunisation Program for children and pregnant women.  

References 

1. Centres for Disease Control and Prevention (CDC). Diphtheria. Centres for Disease Control and Prevention. https://wwwnc.cdc.gov/travel/diseases/diphtheria
2. NSW Health. Diphtheria fact sheet. NSW Government. Updated 14 November 2022. Accessed 29 April, 2024. https://www.health.nsw.gov.au/Infectious/factsheets/Pages/diphtheria.aspx
3. World Health Organization. Diphtheria vaccine: WHO position paper. August 2017 2017;92(Weekly epidemiological record):417-436.
4. Better Health Channel. Diphtheria. Victorian Department of Health Updated 29-08-2017. Accessed 29 April, 2024. https://www.betterhealth.vic.gov.au/health/healthyliving/diphtheria#symptoms-of-diphtheria
5. Health New Zealand Te Whatu Ora. Te rongoā āraimate mō te pakaua hukihuki, te whakapokenga korokoro me te mare tekekō (Boostrix). Tetanus, diptheria and whooping cough vaccine (Boostrix). Health New Zealand.
6. Australian Technical Advisory Group on Immunisation (ATAGI). The Australian Immunisation Handbook. Australian Government Department of Health and Aged Care; 2022.