Why COVID-19 cases are falling in NSW, and why it may be too early to celebrate

New South Wales has hinted at a possible flattening curve in COVID-19 infections, as coronavirus cases fell to their lowest tally since September 1.
But health professionals are hesitant to call the recent decline a trend, as lockdowns and increased vaccinations have helped level the number of infections.
Tuesdayâs update confirmed 1127 new COVID-19 cases in the state, the lowest since 1116 cases were reported on the opening day of September.
Professor of epidemiology at the University of Sydney Alexandra Martiniuk told The New Daily the decrease in cases was reassuring but not definite, with vaccinations and lockdowns stemming the floodgates of cases.
On Tuesday, Dr Jeremy McAnulty from NSW Health said it was too early to know if NSW was flattening the curve.
âMy gut reaction is vaccinations are going up and lockdown is continuing. Itâs what we might expect to see or hope to see, a levelling. But that said, thereâs always perturbations in data,â Professor Martiniuk said.
âLower numbers can tell you a few things: One, it could be true. Numbers could be less, so we may be on a downward trend if that were to continue.
âDid we peak and we are on the mountainside going down? Possibly yes.
âBut there could be other things â the numbers could actually be higher but we didnât test as much and we didnât find as many cases. Or tests could be so slow that people have been tested and the results are sitting somewhere waiting.
âIf we didnât have this lockdown we would be seeing such enormous leaps in the daily case numbers.â

Without lockdowns, epidemiologists suggest NSWâs current COVID-19 case numbers would be far higher. Photo: Getty
Professor Martiniuk said the increased conversations of everyday Australians about the importance of ventilation in workplaces, wearing masks and get a COVID-19 vaccine were driving down case numbers.
Immunologist from the Westmead Institute for Medical Research, Graeme Stewart echoed Professor Martiniuk, saying a few more days were needed to distinguish whether NSW had reached its COVID-19 peak.
From his perspective, the obvious contributor to falling case numbers was that âa significant proportion, particularly in the 12 LGAs, have had the first doseâ.
âItâs likely to be a significant contributor, but I donât think Iâd go beyond that just at this stage,â Professor Stewart told The New Daily.
âGiven 80 per cent of Sydney has been locked down in the 12 LGAs, we may be exhausting the people within those LGAs to go and get tested, the households that have all been tested, and there could well be circulating infection there and elsewhere where people just donât go and get tested.
âI would say itâs encouraging that we could well have turned away from the peak, but itâs a little early yet to be certain of that.â
âNSW at the peak or just approaching itâ
According to Chair of Biostatistics and Epidemiology at the University of South Australia Adrian Esterman, not only can it be called a trend, but it also shows NSW has either reached or is just reaching the peak.
Professor Esterman tracks the effective productive number also known as Reff or R0, of COVID-19, which dropped down to 0.95 from 1.15 this week.
The Reff describes how fast the virus can spread to other people.
For example, a Reff number of two means each positive case of the virus is passing it on to an average of two people.
âToday, NSW got down to 0.95, so thatâs really good news and it basically shows that things are starting to slow down and, even better, still starting to fall,â Professor Esterman told The New Daily.
âWhat we are saying is that if the current trend carries on the way it does, and nothing else changes apart from increased vaccinations, I suggest that NSW is either at the peak or rapidly approaching it.â
The professor agreed vaccination rates and a continuing lockdown had been a significant driver to lower case numbers and Reff numbers.
âIt means that things are looking a bit brighter, it does mean that these various restrictions can very slowly and carefully be relaxed, which is what the NSW government will be doing. It will mean more freedom, especially for those that are fully vaccinated.â








