Covid 19 coronavirus: Top scientist shuts down ideas the virus never left New Zealand

A top scientist remains firm that New Zealand did eliminate Covid-19 saying it is very unlikely the virus has been in communities for months.

"Scientists would never say impossible but I can say it's completely implausible," epidemiologist Michael Baker told the Herald.

He said there were three key reasons why that theory didn't add up:

1. "Thousands of people in New Zealand have been tested every day and until now, not one has resulted in a positive result."

2. "We know that there is always a proportion of people who get sick that will go to the hospital, about 10 per cent, yet we have seen no cases of the virus at our hospitals."

3. "Covid-19 is a very infectious virus - for each person that is infected another two to three people will likely transmit the virus. That means we would see an outbreak very quickly."

When asked what would be the tipping point for Auckland, and the rest of the country, to move to alert level 4, Baker said he couldn't comment on that.

"The most important thing is that we find out how many people have been infected and make sure they are isolating."

When asked how many people would need to be infected for the country to move to alert level 4, Baker again said he could not comment on that.

Epidemiologist Michael Baker says there is almost a zero per cent chance Covid-19 had been lingering in the community earlier than known. Photo / File

He advised people to be cautious about reading false information on social media.

"People need to make sure they are engaging their brains and thinking critically. Don't accept statements by anyone without critically assessing it.

"Even as a scientist I expect people to critically assess me. That's the nature of science, you put your ideas onto a forum and they are reviewed by peers and multidisciplinary review and if people disagree with your logic they will challenge that very quickly.

"As opposed to putting out ideas that don't have a scientific base and are not on a forum where they can be reviewed from a science point of view."