Record Covid cases in NSW overshadow other statistics which reveal the outbreak will inevitably get worse
The headline figure that New South Wales had reported a record 633 new Covid cases obscured some other truly terrible statistics in the latest press conference by the NSW premier, Gladys Berejiklian. These reveal some alarming trends.
The first of these was the revelation that the current reproduction number of the virus, its R factor, is 1.3 – well over the rate of 1.0 which is needed to stabilise case numbers. At present, each positive person is infecting 1.3 others.
That means numbers will inevitably get worse – potentially a lot worse – and that NSW is in danger of completely losing control of this Delta wave.
The second troubling statistic revealed on Wednesday suggests NSW’s much-vaunted “gold standard” contact tracing system is under severe strain.
Only one-quarter of the new cases were immediately linked to previous cases: 145 were household contacts and 13 were close contacts. The source of infection for 475 cases was still under investigation. That means we are flying blind, possibly for days, regarding where and how the virus is transmitting.
A third set of scary numbers suggests testing and outreach are slowing down under the weight of this outbreak, which started in mid-June.
There were 102,749 Covid tests in the latest 24-hour period compared with the previous day’s total of 151,767 tests. Generally, testing in NSW has been running at about 150,000 to 160,000 tests a day, turbo-charged in recent weeks by the requirement that authorised workers leaving hotspot local government areas be tested every three days.
It’s hard to believe that in the midst of such an outbreak, testing numbers have declined. So what’s going on?
On Tuesday, the state’s chief health officer, Dr Kerry Chant, acknowledged that at least one pathology company was struggling to report results in a timely way. But if the testing labs are under strain, then we urgently need to triage people to make sure those most at risk are tested faster. That might mean in hotspots and health workers.
The other problem is the number of people infectious while in the community. On Wednesday, NSW Health reported 62 cases were infectious in the community, 32 were in the community for part of their infectious period and the isolation status of another 447 cases was under investigation.
This means the government doesn’t know whether three-quarters of the new cases have been at home or not.
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The state government announced earlier this week it was now using texts instead of a phone call to notify people of their positive diagnosis, because staff were overwhelmed. It all points to a system that is slowly breaking down and that it is taking longer and longer to make personal contact with people who are Covid-positive.
Given that clusters are in communities that have English as a second language and who do not necessarily have savings that permit them to stay home, these are really serious problems.
We also learned this week that NSW Health had stopped publishing low risk exposure sites in greater Sydney. Up until the weekend, the health advice had been to check the department’s website regularly and get tested if a venue you had attended was listed.
The sewage surveillance system provides another way to know if a Covid-positive case has used a toilet in your area – but only about 60 of 157 sewage sites are currently being tested. So it’s an incomplete picture.
It’s not clear what people should do. Having spent the past few months checking exposure sites to gauge how close Covid is to them, they will need to rely on hotspot and suburb notifications.
In the case of close contact exposure requiring 14 days isolation, presumably the government will ring or text, based on QR codes or other checkin records. But there is plenty of anecdotal evidence that this process is slowing as well.
The rising case numbers have inevitably led to calls for a tougher lockdown, more policing and bigger fines.
But as Prof Marylouise McLaws, an epidemiologist from the University of NSW and a member of the World Health Organization’s emergency response program, says, what we really need is much more granular information to understand where we need to put our efforts.
If you listen to the NSW daily press conferences, you’d be forgiven for thinking that lawless, maskless mobs are rampaging in hotspots.
But as we learned this week, most of the new cases – 70% – are due to transmission within households in the hotspot areas, many of which are large households where English is not the first language.
“What we are seeing is workers from those areas … working in factories and cleaning and other things, going into workplaces, leading to transmission and then transmission occurs and then a seeding of another household,” Chant said on Wednesday.
“We also know that some people, a small proportion of people, are not, perhaps, taking Covid as seriously as I would like them to do. And then what’s happening is they’re potentially going into multiple households.
“So, for instance, you might have one person who has connections across three households, but in each of those households, you have got tens of people.”
If this is the problem, then McLaws suggests that the solution might lie in putting security guards or community members outside infected houses to stop other households visiting. The government has expanded its network of health accommodation in Meriton Suites in the inner west for people who cannot effectively isolate and that’s a good step, but we need to focus on the high-risk problems.
“Police found at least 400 examples in one day of people leaving their home when they shouldn’t be. What worries us is for every person we find doing the wrong thing, there could be somebody else doing the wrong thing,” Berejiklian said.
The tougher policing effort might stop people visiting each other but the real risk, according to Chant, is infected families visiting each other – and that’s likely to be occurring in suburban streets.
Calls for curfews, similar to the one in Melbourne, will only be useful if the visiting is predominantly occurring at night. That requires facts and data, which is short on the ground in NSW.
The other problem identified by Chant is authorised workers infecting each other, and then seeding new households. The NSW government is prioritising them for vaccination, which is wise, but this will take time.
McLaws suggests that rapid antigen testing in workplaces could help drive down case numbers in the interim. She says many of the test brands are accurate in identifying positive cases but throw up false positives, which means some workers may be off work while they have a follow-up PCR swab.
More recently childcare centres have emerged as a problem. But is it family daycare or large centres? Is it transmission among staff, children or parents?
We don’t know, unfortunately, because we are getting less information about the shape of the outbreak in NSW, not more.
It might be necessary to strictly limit childcare only to the children of authorised workers. Or it might be solvable by rapid antigen testing.
If the government wants to take the community on this journey it needs to inform and educate – not just impose rules. The Coalition also needs to level with us about how long and arduous the journey might be rather than offering false hope that September will be better.