Another COVID wave could emerge in summer, Dr David Durrheim says

The latest NSW Respiratory Surveillance Report said Hunter New England recorded 54 influenza cases for the week ending October 7.

This fell from a high of 456 notifiable cases in the week ending July 8.

"We expected flu to go away and it has. So it's behaving like it normally does," Dr Durrheim said.

"And we expect the rhinoviruses - the cold viruses - to go away. There's still a low level of activity of COVID around and we know we're probably vulnerable to another wave.

"Once you get three months past the previous wave, and we're well past that, then there's the possibility of it taking off."

He said it was unknown whether COVID would "behave like normal respiratory viruses".

The expected gap between waves of the virus was also unknown.

In the week ending October 7, there were 71 COVID cases recorded, which applied only to notifiable PCR lab tests.

This latest flu and COVID data comes from people with respiratory illnesses who are unwell enough to seek medical attention and be tested.

More than 2030 COVID cases were recorded in the Hunter New England health district in the week ending May 20, although this was when people were self-reporting positive tests.

The Newcastle Herald reported on Thursday that a gastro outbreak was widespread across the Hunter New England district with 24 child-care centres affected.

Dr Durrheim said gastro viruses "do go away as we head into summer".

"The big issue will be salmonella, a bacteria which often causes food poisoning from foods that aren't kept hot or cold, with our lovely summer picnic weather," he said.

It was reported last week that people travelling to Bali will be screened for Nipah virus, after cases of the deadly zoonotic illness were confirmed in India with at least two deaths.

"There's a big outbreak at the moment in India. Nipah is very similar to Hendra virus. It's the same family of viruses," Dr Durrheim said.

Nipah virus can be transmitted to humans from animals such as bats and pigs.

"There are people who visit areas in outbreak mode and might come into contact with it, but it's unlikely. We haven't ever had Nipah virus in Australia."

Hendra virus infects fruit bats [flying foxes]. Occasionally the virus can spread from flying foxes to horses and, in rare cases, horses have passed the infection on to humans.

"Clearly we can't be naive. We have to keep high levels of surveillance, particularly with viruses that might spill over from bats."

He said SARS-CoV-2, which causes COVID-19, originated in bats.

"And we have bat lyssavirus, rabies virus and Hendra that circulate in bats," he said.

"Bats are fascinating. They're a remarkable source for exotic viruses.

"Their immune systems are so adaptive that they quickly evolve to a point where they no longer become ill, but may well become a reservoir for a virus."

Mosquitos aren't expected to be as prominent in the hot and dry conditions ahead.

"In high risk areas like Hexham Swamp or Blackbutt Reserve, it's still worth slapping on mosquito repellant."

IN THE NEWS