Dr Siouxsie Wiles is blasting any Aucklanders who fled the city to avoid the lockdown, saying it's a "shitty thing to do".
Prime Minister Jacinda Ardern announced on Saturday night that following a new community case Auckland would return to alert level 3 and the rest of New Zealand to alert level 2 for a week, starting 6am Sunday.
This led to reports of an exodus of Auckland residents keen to avoid being cooped up in the city.
But that has drawn a frustrated response from the Auckland University microbiologist who is concerned they could bring the virus with them.
"Hey, all you Aucklanders leaving the city during the night to spend the week at your bach... you better bloody well take level 3 with you. You do realise this is a shitty thing to do? If you are incubating the virus you run the risk of spreading it outside Auckland," Dr Wiles posted to Twitter.
"I know you all feel fine and don't think you have the virus, but that's how everyone incubating COVID-19 starts off. You could be setting off chains of transmission and potentially in places with far less healthcare capacity than Auckland."
Dr Wiles elaborated to Stuff that even if Aucklanders escaping before the 6am lockdown kicked in weren't breaking the law, they were going against the spirit of the rules.
"What I'm really worried about is people who have potentially been exposed, and are now in a different part of the country [to Auckland] and are now under a different alert level, and if they're in places that don't have a large health infrastructure to support a number of COVID cases."
Dr Wiles added that these Aucklanders should come home, and make sure they all obey the alert level 3 rules in place for the Auckland region.