Dr John Boffa, a Northern Territory GP and public health medical officer, learned that diphtheria was spreading through his community in late March - several months after the outbreak actually began. “By the time we became aware of it, it had been grumbling along for some time,” said Boffa, who also serves as chief medical officer for the Central Australian Aboriginal Congress Aboriginal Corporation in Alice Springs. At that point, Northern Territory Health was aware of 37 cases of cutaneous (skin) diphtheria - which had been quietly emerging since May 2025 - and four cases of the more serious respiratory diphtheria, two in Darwin and two in Alice Springs, all diagnosed in March.

“I quickly then learned about all the cases that had been in Darwin since last year, and at that point our case here in Alice Springs was not linked to the Darwin outbreak,” Boffa said. “Then it was obvious it was everywhere, because if you’ve got unlinked cases, it’s all around us.” Congress kicked into action, but when outreach teams visited town camps to immunise, they discovered that the community lacked basic information about diphtheria’s severity, how to get vaccinated, and when to get a booster - which for health workers and Indigenous people is recommended every five years. There was also an initial struggle to secure enough vaccine supply. By May, 15 to 20 new cases were being diagnosed each week, and the single lab at Royal Darwin Hospital took up to a week to return results.

“We finally got over that vaccine supply issue by the end of last week,” Boffa said. “We didn’t have a major vaccine hesitancy issue, and once people were informed they were happy to get vaccinated. We were actually impeded by workforce. It’s not like you can sit in the clinic and wait for everyone to come to you - that won’t happen in remote communities.” The outbreak has now ballooned to more than 230 cases, including at least 85 in Western Australia, seven confirmed on the APY Lands in South Australia, and several in Queensland. Up to one-third of cases have been hospitalised with respiratory diphtheria, and most cases are in Indigenous adults - a stark reminder of ongoing overcrowded housing and poor living conditions. Northern Territory Health reports 50 hospitalisations since January, with four patients in intensive care. For context, prior to this outbreak, Australia saw six or fewer diphtheria hospitalisations annually since 1999.

Brenda Garstone, CEO of Yura Yungi Medical Service Aboriginal Corporation in Halls Creek - a community of 4,000 on the edge of the Great Sandy Desert - says her small health service is already stretched. “We’ve got a small community, so it’s inevitable that it’s probably going to spread a bit more,” she said. More than a third of recorded cases are in children and teenagers. Contact tracing and uncertainty over whether Covid-era funding for a dedicated vaccination officer will continue add to the pressure. “It was eradicated for so long, and it’s been so many decades since it was around that people don’t really know what to look for,” Garstone added.

In Queensland’s Yarrabah community, medical services are on standby, with a public information campaign underway to raise vaccination rates that dropped slightly post-Covid from over 95%. Dr Jason King, a Yued Noongar man and director of clinical services at Gurriny Yealamucka Health Service, said: “Our rates have started to climb back up to where we need them to be, but it’s still a pretty uphill battle.” In April, Boffa’s partnership of organisations applied to the federal government for funding. When support still hadn’t arrived by 16 May, and with the Northern Territory recording its first diphtheria death in more than a decade (an adult in a remote area, cause pending coroner confirmation), Boffa told the ABC: “I felt like everything was taking too long. One of the lessons we’ve learned with communicable disease is you’ve got to go hard, go early. Once you let the genie out of the bottle, it’s very hard to put the genie back in.”

On Thursday, the federal government announced a $7.2 million package, including funds for a surge workforce and additional vaccines and antibiotics. “It’s actually more generous than what we originally asked for, which is fantastic,” Boffa said. He doesn’t blame the government for the delay but questions whether the application should have been made sooner. He notes that early cases were cutaneous diphtheria - rarely life-threatening - which may have created less urgency, even though it can cause chronic ulcers and spread to cause respiratory disease. Ongoing booster campaigns are critical, given vaccination rates for Aboriginal and Torres Strait Islander five-year-olds sit at 94.33%. “I think if we get boosted rates up to where they need to be, and once we’re able to more effectively contact-trace and treat with antibiotics, then we should start to see this outbreak dissipate,” Boffa said. “I think, though, we’ve got to get better at this … Particularly when it’s in Aboriginal communities affected, the community-controlled sector needs to be engaged right up front.”