The NT has recorded 84 cases of diphtheria since January 1 last year, NT Health said on Tuesday, with 66 of those cases involving skin sores, as incidents of the uncommon bacterial infection that can cause severe illness in unvaccinated individuals continues to grow.

Of the 84 reported cases between January 1, 2025 and April 24, 2026, the remaining 18 cases were highly contagious respiratory diphtheria.

NT Health said cutaneous diphtheria can cause skin sores, while respiratory diphtheria cases cause sore throats, both of which can be treated with antibiotics.

The latest public health statement follows the declaration of an outbreak of diphtheria last month.

Locations of where the cases have been reported was not disclosed by NT Health.

“Diphtheria is spread by direct skin contact with people who have infected sores or by coughing and sneezing from people who have respiratory diphtheria,” authorities said in a statement.

“Vaccination is the most important health measure for prevention, protection and reducing transmission.”

Symptoms include a sore throat or swelling, fever, difficulty swallowing or breathing, and infected or non-healing sores.

Cleaning and covering skin sores, proper hand hygiene and covering the mouth when coughing and sneezing can help prevent diphtheria from spreading.

Vaccination is free under the National Immunisation Program for people under the age of 20. Children receive routine vaccinations against diphtheria at six weeks, four months, six months, 18 months, four years and 12 years, the government said.

Pregnant women from 20 weeks are also eligible for a free vaccination.

NT Health recommends adults have a diphtheria vaccine booster every 10 years and those without are urged to check with their health care providers.

“Territorians can get the vaccine at their local Aboriginal health service, remote community clinic, community care centres, GPs, and participating pharmacies,” NT Health said in the latest statement.

“See your health service/GP if you are concerned about your symptoms.”

More information is available at the NT Government’s diphtheria website.