A new "mini cluster" of Covid-19 cases in Auckland identified yesterday is concerning to see on the cusp of the city lowering alert levels, a microbiologist says.
Five people associated with the Mt Roskill Evangelical Fellowship have tested positive in the past two to three days.
Director general of health Ashley Bloomfield urged anyone who was at the services held at the church on Stoddard Rd on August 8, 9 and 11 and a wedding on August 7 to isolate and seek a test.
"They're all connected to each other but we haven't found the epidemiological link to the cluster and we're waiting for the whole genome sequencing. We believe they will be linked to the cluster, we haven't got the epidemiological link yet, so they're like a mini cluster at the moment."
Auckland University microbiologist Siouxsie Wiles told RNZ that genome sequencing would be crucial to scientifically prove whether it was in fact linked to the cluster.
"My concern is that if we can't find the link, that suggests there might be some other transmission chains and the question is whether we stopped those or whether once we move down to level 2 they'll continue. That's why all the testing that's happening at the moment is really, really important.
"The more sort of loose ends we see, the more concerned I am about moving out of level 3 here in Auckland."
Ensuring there was no further community transmission was key to moving down alert levels, Dr Wiles said.
"What concerns me is that I know we all want to be out of restrictions as soon as possible, but if there is transmission still happening and we move to level 2 then at level 2 much more transmission can happen and we'll see more cases rising but we won't see them maybe for a week or two.
"What we don't want is a large amount of uncontrolled transmission again which requires us to be back in alert level 3."
Although the dates Dr Bloomfield talked about were from about two weeks ago, this appeared to be in line with evidence on the lag between being infected and illness showing, Dr Wiles said.
"It may well be that people had very mild symptoms and so didn't think to go get tested until recently.
"It's getting on the margin of transmission happening and that's why we need to be clear, is this part of the main cluster? Where did that transmission happen?"
While events and gatherings like weddings could be breeding grounds for the virus, Dr Wiles said it was down to everyone to continue practice hygiene and other public health measures to minimise chances of transmission.
"I've been watching people who really don't understand what two metres is, and we know the masks will be helpful especially in indoor environments, and so I do worry when we move to level 2 that we'll be doing lots of things where if there is still community transmission happening, we'll be helping it along."
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