A threat hangs over the trans-Tasman bubble on Tuesday night thanks to a new case of COVID-19 at New Zealand's border.
The Auckland Airport worker's infection takes the number of system failures leading to new cases to 15 since July last year.
It's a rate GPs and epidemiologists say is too high and that New Zealand must improve.
The latest case is a worker who cleaned planes carrying high-risk passengers. They tested positive for COVID-19 on Monday and were fully vaccinated against the virus.
The threat to New Zealand has always been at the borders, on the red-zone planes, and within our managed isolation and quarantine (MIQ) hotels - and on just day two of the trans-Tasman bubble, another breach.
"This is an individual who boards planes to clean them after they've come from places where there is COVID, carrying passengers with COVID," Prime Minister Jacinda Ardern said on Tuesday afternoon.
Bryan Betty, the medical director of the Royal New Zealand College of GPs, said it's possible the country will see more situations like it in the future.
"So the vaccine is thought to be about 95 percent effective, which means about 5 percent of people - or one in 20 - could potentially still get COVID," Dr Betty said.
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What's not known is whether the cleaner could still transfer the virus to others. Dr Betty said that's possible, which is why contact tracing needs to happen.
There have been 15 border failures since July - three COVID-19 cases every two months on average. Of those, 11 cases were failures at our MIQ hotels and four others were non-MIQ related, like the airport cleaner or an air crew member getting the virus.
"This is way too high. We should be tightening our systems to really reduce border failures to make them really rare events," said Otago University epidemiologist Professor Nick Wilson.
"It is concerning that these cases keep happening and they are really putting the success of the trans-Tasman bubble at risk."
But Prime Minister said the latest case shows how transmissible the virus is - and as it's linked to the border, it won't stop the bubble.
"These are the kinds of scenarios where we would anticipate movement continuing," Ardern said. "It is by no means a leaky border if someone cleaning a plane carrying people with COVID becomes infected."
Australia also remained confident.
"They're on to this. We have full confidence in New Zealand's systems.
"We've seen them deal with the inevitable outbreaks," said Australia Health Minister Greg Hunt.
But Prof Wilson said the new case does show a breakdown in New Zealand's systems to keep COVID-19 out.
"What we're seeing with these border failures is a failure of the design and implementation of those systems."
Dr Betty agrees.
"Every time this happens we need to learn from it. We need to learn from it and incorporate it.
"We need to reduce the amount of breaches that are occuring."