People who were at a Northland supermarket are asked to keep a close eye on their health after contact tracing revealed a person with coronavirus shopped there.
Anyone who was at New World Kaikohe between March 20-30 may have been exposed.
However, people will only be tested if they display symptoms of Covid-19, health officials say.
"Testing well people can create a false sense of security," Northland DHB Medical Officer of Health Dr Catherine Jackson says.
"Just because you test negative today, doesn’t mean you won’t get Covid-19 and test positive another day. The best time to be tested is if you have symptoms."
There have been 14 cases in the Northland region, with one of them being treated as a probable case but not yet concerned.
Four people have recovered but 10 others are in self-isolation.
No one has been hospitalised in Northland, Northland DHB says.