Staff members at the Far North District Council and Top Energy are among the Northlanders diagnosed with the Covid-19 virus.
Mayor John Carter made the announcement at a council meeting conducted by video conference earlier this month.
Both have since recovered and are now working from home.
Carter said the staff member had gone into isolation after being found to have Covid-19 about two weeks ago.
Before developing symptoms the staffer had ''done a little bit of shopping, etc, so that is an issue for us''.
Carter would not say what the staffer's role was but said the public had not been put at risk through dealings with the council.
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Carter said Far North lines company Top Energy and contracting company Broadspectrum also had workers who had tested positive. A case of Covid-19 at New World in Kaikohe had already been widely reported.
''The point I'm making is that it's in our community, it's amongst us, so we have to be aware, alert and careful,'' he said.
Top Energy chief executive Russell Shaw said a staff member at the Kerikeri office had tested positive but had fully recovered and had gone back to working from home on Monday. The staffer did not require hospital treatment.
Shaw said nine work contacts had gone into isolation and the office had been sanitised.
All had tested negative which he put down to good social distancing within the workplace.
All office staff were now working from home, he said.
Field staff were continuing to work — ''we still have to keep the power on'' — but were disinfecting tools between jobs, maintaining social distancing and staying within their own work bubbles.
''The guys have been very careful and are doing an excellent job. They don't want to take this stuff home.''
Carter told councillors to expect strict rules about how people interacted even after the level 4 alert was lifted.
''Handshakes and hongi will not be part of our community for some serious time,'' he said.