A Sydney-based clinical immunologist has shared a sobering view of how Christmas could turn into a superspreader event that could overwhelm the hospital system. 

In a 17-minute video posted to Facebook, Dr Dan Suan said NSW is "sleepwalking into an Omicron disaster" if no changes are made to curb infections in the six days leading up to Christmas. 

"We risk turning Christmas Day into a simultaneous super spreader event all across Sydney in thousands of houses," he said. "And if everyone catches Omicron on Christmas Day, there will be a hospital-based disaster in early January. 

"2400 cases today mean there are several thousand more people already infected, they just haven't tested positive." 

Cases of Covid-19, particularly the Omicron variant, have been increasing across multiple states and territories. 

NSW today recorded 2501 new Covid cases, slightly down from Sunday's 2566 - a daily record for the state and for Australia throughout the pandemic. There are now over 300 known Omicron cases across the state, though NSW Health warned the majority of Sunday's cases were likely the Omicron variant. 

NSW's cases have been spurred on by multiple super-spreading events at pubs and clubs, particularly in Newcastle and Sydney. 

Yet last week, restrictions around mask-wearing and QR code check-ins were eased, with both safety measures now only required in certain "high-risk" settings. 

NSW Premier Dominic Perrottet has said the government will keep a close eye on the number of people in ICU. Photo / Getty Images 

Describing the situation as a "problem of pure maths," Suan, said in the increased transmissibility of Omicron and its resistance to vaccines means it has the potential to cause a massive outbreak. 

"It can infect virtually everyone," he said. "Virtually the entire Sydney population is at risk of catching Omicron." 

Despite the fact 93.4 per cent of people aged 16 and over are vaccinated in NSW, Suan said only people who have a "normal immune system and have been triple vaccinated" are adequately protected. In doing so, he discounted people who are merely double-jabbed, immunocompromised and children under the age of 12 who are likely unvaccinated. 

"Omicron is much more contagious than Delta or anything else we've seen before," he said, "The mutation in the virus means that it is able to stay in the air much longer and the consequence of that is that one person can infect many more people." 

He also warned against over-estimating the supposed decreased severity of the new variant, adding that there's "no good evidence" on whether this is true. Dr Suan also said that the benefits offered to be a strain that is less severe would become irrelevant if a large outbreak in cases resulted in an overwhelming number of hospitalisations. 

"Omicron might be slightly less severe but if the outbreak is huge and you put those things together, we'll still have a huge number of people needing to be hospitalised," said Suan. 

"It will overwhelm the hospital system easy." 

Finishing the video, Dr Suan shared five recommendations on how NSW could avoid a severe Christmas outbreak, including mask-wearing indoors, reconsidering upcoming events, increased testing, and pushing forward with booster shots. 

'It is scary times' 

On Sunday night, the health expert appeared on Channel 10's The Project where he cautioned that there is a looming "hospital-based disaster" due to the "profound public health threat" posed by the highly-mutated strain. 

"The Omicron variant has some characteristics which mean that it is a profound public health threat and, because of our social mobility at the moment, it's spreading very quickly," Suan told the programme. 

Suan's warning prompted host Hamish Macdonald to admit "it is scary times" for Australians, particularly with a number of Covid restrictions recently easing. 

Dr Suan appeared on The Project and told host Hamish Macdonald his sobering predictions for the week ahead if no changes are made. Photo / The Project/Channel 10 

Macdonald also pointed out that there were some infectious diseases specialists that had differing views to those that have been issuing pessimistic warnings about the growing Omicron cases. 

"There are experts, though – like Peter Collignon and Nick Coatsworth, for example – who are hitting back at what they say is some alarmism about the Omicron variant," The Project host said. 

"I mean, is there a risk that this is stoking unnecessary fear?" 

However, Suan claimed enough data had now been gathered about the Omicron variant to know how much of an impact it could potentially have. 

"We know how contagious it is; we know that it escapes the vaccines, and we know how quickly it spreads. Because we can already see that by the vertical nature of the case curve here in Sydney," he said. 

"If you infect enough people with Omicron, a certain proportion of people need to go to the hospital. That proportion is reduced by vaccines – that's the whole point – but not enough. 

"The Omicron variant means that the protection from severe disease falls, and it falls sufficiently so that if you infect enough people, you still have a huge number of people that will need to go to hospital – a number that well exceeds the hospitals that are ready to cope."