Coronavirus: mystery cases have officials puzzled

A series of mystery cases emerging across Sydney has left health authorities struggling to find the missing pieces of the state’s coronavirus puzzle.

‘What we’re looking for is the missing link’: NSW chief health officer Dr Kerry Chant. Picture: NCA NewsWire / Gaye Gerard

A series of mystery cases emerging across Sydney has left health authorities struggling to find the missing pieces of the state’s coronavirus puzzle.

Five locally acquired cases were recorded on Monday, four of which were linked to the Avalon cluster now responsible for 126 cases and one of which is linked to a case on the northern beaches yet to be linked to the Avalon cluster.

Chief health officer Dr Kerry Chant has urged Sydneysiders to come forward for testing after confirming that NSW’s five mystery cases, reported on Sunday, were linked to unknown sources.

“Even if you historically had an illness that you think in ­retrospect might have been ­compatible with COVID, please get a test and please isolate until you get that negative test,” Dr Chant said.

Those tested positive with unknown sources were a Belrose Hotel worker, a Crows Nest firefighter, a Manly commuter, a Bondi resident, and a man who visited the Sydney CBD.

The Belrose Hotel staff member, 20, was tested on December 23 but a serological examination traced his infection back to December 10, leaving health authorities questioning whether he was the earliest known case for the Avalon cluster.

Several new cases have been linked to the Belrose Hotel in Sydney’s northeast. Picture: NCA NewsWire / Jenny Evans

Further up the northern beaches in Mona Vale, a firefighter tested positive for the virus on Christmas Day after he received an initial negative result on December 20. On December 11, he had spent an hour and a half at the Belrose Hotel.

Despite the apparent link, the young worker was not on shift the night the firefighter visited the hotel, and so far all his co-workers have tested negative. Contact tracers therefore concluded he could not have been the source of the firey’s infection.

Another positive case entered the Belrose Hotel bottle shop on December 17, however, Dr Chant said this case also could not be linked to the employee who wasn’t working at the time.

“What we’re looking for is the missing link,” Dr Chant said.

“Who else was present at the Belrose?”

Authorities were awaiting results from genome testing from the Belrose cases to determine whether they are directly linked to the Avalon cluster.

A man who visited Chifley Square in the Sydney CBD also tested positive with no known source. While he was there at the same time as other confirmed cases, they never crossed paths.

On Boxing Day, a Bondi resident was diagnosed with the virus but is now believed to be a false positive.

Dr Chant has engaged an expert panel to review all information regarding the case.

The fifth untraced case was a man who worked in the southern end of the northern beaches in Manly and commuted into the area. His Opal card data was being analysed for any overlap with other infectious cases on his bus routes.