North Coast Public Health director Paul Douglas said there was no ongoing risk to the broader community, but families should be alert and review their children’s immunisation status.

“Diphtheria is very rare in Australia due to our longstanding childhood immunisation program. However, the disease has very serious outcomes and can be fatal,” he said.

“The diphtheria vaccination is free and readily available from your GP for everyone from six weeks of age.”

Diphtheria was a common cause of death in children up until the 1940s but it now occurs mainly in countries with poor immunisation levels, according to NSW Health.

The infection is spread through coughing and sneezing, and can also spread by contact with contaminated surfaces.