Bird flu could become the next human pandemic, Newcastle-based disease experts say.
"It's definitely possible," infectious diseases physician Joshua Davis, of the Hunter Medical Research Institute (HMRI), said.
"It seems pretty unlikely right now because the sequence of the bird flu virus they've found in birds and seals doesn't have any genetic markers of adaptation to humans, but it could happen.
"If it did happen, it would be really bad because it's very pathogenic. It's an aggressive virus."
Professor Davis's comments come ahead of an HMRI event on Friday night to consider preparations for the next pandemic.
HMRI's infection research program will screen the film Contagion at Tower Cinemas Newcastle, followed by a live Q&A with some of Australia's top infectious disease experts.
Professor Nathan Bartlett, who will be among them, agreed that it was "definitely plausible" that bird flu could become a human pandemic.
"We've seen this before. You can get different influenza viruses in a single host, like a pig," said Professor Bartlett, an HMRI virologist.
"If we look at the origin of the swine flu pandemic, that happened because different flu viruses mixed together in pigs. You had human, pig and avian viruses.
"They can swap segments and you can get this whole new virus that retains the ability to transmit between humans, which your immune system doesn't recognise. That's a worse case scenario."
Such a nightmare scenario, though, was "impossible to predict".
"We need to be vigilant and have good surveillance," Professor Bartlett said.
The World Health Organisation (WHO) said "currently circulating zoonotic influenza viruses have not demonstrated sustained human-to-human transmission".
"There will be influenza pandemics in the future, but which virus, as well as where and how they will spread, is difficult to predict," a WHO statement said.
Professor Davis said the first thing about preparing for the next pandemic was "to know a pandemic is happening".
"It sounds obvious, but it's not always obvious. We get hundreds of thousands of flu and flu-like illnesses every year," he said.
"If a new virus comes in that's not detected by our usual tests, all we'll know is there are lots of people with fever and cough and we don't know what they've got."
Hunter health officials are involved with a surveillance system called FluTracking to monitor respiratory illnesses and "pick up unusual signals".
"We get FluTracking participants to have regular PCR tests. If they have symptoms and there's nothing that shows up in usual tests, their samples are used to look for known or unknown viruses with metagenomics," Professor Davis said.
He said the aim was to establish this "as ongoing surveillance".
"If this system is set up, you'd see a little signal of people getting sick that don't have any of the common viruses. So we'd have a look and sequence the DNA in their nose to look for a new virus," he said.
"Another part is working with viruses in the lab to try to work out treatments that can help prevent infections. There's vaccines but also drugs you can squirt up your nose that make you resistant to catching colds and flu."
This includes a milk protein called lactoferrin, which has "immune-boosting activity and inhibits viral infections".
Meanwhile, the latest NSW Respiratory Surveillance report was released on Thursday.
It found that influenza activity decreased but remained at a high level, COVID-19 remained at a low level and RSV remained at a moderate level.
"ED presentations for influenza-like illness and admissions decreased," the report said.
The report showed 637 positive tests for influenza, 190 for RSV and 56 for COVID in Hunter New England in the week ending September 12. These results apply to people sick enough to be tested.
"It's been a good season. We've had less flu and COVID," Professor Davis said.
"A couple of months ago, people were saying we'd get a big late surge of flu. I don't think that'll happen. It looks to me like it's already turning the corner. I think we've had our peak of flu this year."
Professor Davis said "COVID has become a minor player now".
"Firstly, we have widespread population immunity. Most of us have had COVID once or twice. And most of us have had at least one round of a COVID vaccine," he said.
"Secondly the virus has evolved to be less virulent."
He said Contagion predicted many of the issues that happened during COVID, including "accelerated vaccine development and widespread public mistrust of the vaccine".
"Whatever vaccine it is, there will always be a big vaccine sceptic group in the community. The unfortunate thing with COVID vaccines was there ended up being some safety problems, but they were rare, like myocarditis and blood clotting for example," he said.
He said the COVID vaccines saved many lives.
