![STUDY: The Argyle "Prom Night" on December 8 spread Omicron rapidly through the Lower Hunter and beyond. STUDY: The Argyle "Prom Night" on December 8 spread Omicron rapidly through the Lower Hunter and beyond.](/images/transform/v1/crop/frm/TFWurqJd3WWgt5tunziPf4/3b0b25b3-2944-4b94-afc5-b0f3de8d2650.jpg/r0_501_5128_3395_w1200_h678_fmax.jpg)
A new study on Newcastle's Omicron outbreak in December shows more than half of those who attended super-spreader events at Argyle House and NEX later tested positive.
Subscribe now for unlimited access.
or signup to continue reading
The research shows two men who were meant to be isolating infected 55 per cent of the young people who partied at Argyle House's "Prom Night" on December 8.
Of the 535 revellers at the nightclub who later had a PCR test, 295 returned a positive result.
The two 20-year-old men were later fined $15,000 for breaking isolation rules after contracting the virus at a Sydney Harbour boat party five days earlier.
The nightclub event seeded another outbreak two days later at a medical ball at NEX and kick-started the Omicron wave in the Hunter and later the rest of NSW.
The high positivity rate at Argyle House demonstrated the Omicron variant's extraordinary ability to jump from one person to the next.
The infection rate at the University of Newcastle medical school graduation ball was 54 per cent, or 102 out of 189 attendees.
More than 95 per cent of those at the two events were double-vaccinated.
None of those infected were admitted to hospital due to COVID-19, but the study authors said their young age meant they could not be compared to the general population.
The average ages of the Argyle House and NEX crowds were 21 and 26 respectively.
The study authors, led by University of NSW's Dr Bette Liu, found the Omicron variant caused "high attack rates" in a two-dose vaccinated population in the "high-risk" indoor settings.
They said the outbreaks had occurred in environments where "social restrictions were absent, there was no mask wearing, nor strict control on density limits".
"Activities conducive to virus transmission occurred, particularly at the nightclub with energetic dancing, drinking and close face-to-face contact in mostly small, crowded and poorly ventilated rooms with few external open windows," they said.
Associate Professor Liu said the study showed recent vaccination with two doses was moderately effective in preventing infection with the Omicron variant but this varied depending on the setting.
"Social restrictions are needed in high-risk indoor environments, in addition to two doses and a booster, to reduce infection risk," she said.
The study found no difference in effectiveness between the Pfizer and AstraZeneca vaccines at the two clubs.
The study, which has been posted on The Lancet medical journal's pre-pint website and is yet to be peer-reviewed, was conducted by researchers from the National Centre for Immunisation Research and Surveillance, the NSW Ministry of Health, Hunter New England Local Health District, University of Newcastle and University of Sydney.
Hunter New England health protection director Dr David Durrheim said two vaccine doses gave moderate protection from hospitalisation with Omicron. This waned after two or three months then increased significantly after a booster shot.
"Just as important, our study reinforces the need for the public health measures, including wearing masks indoors, on public transport and in schools; density limits; increased ventilation; and restrictions on dancing and singing," he said.
The NSW government ended restrictions on singing and dancing last week and will remove mask mandates for nightclubs and most other venues on Friday.
School children will not have to wear masks from next week.
In the news
Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content:
- Bookmark: newcastleherald.com.au
- Download our app
- Make sure you are signed up for our breaking and regular headlines newsletters
- Follow us on Twitter
- Follow us on Instagram
- Follow us on Google News