A second staff member at Enner Glynn School has tested positive for Covid-19.
In a post to Facebook, principal Isaac Day said they received confirmation from the Medical Officer of Health about the new case.
The staff member is considered to have been infectious from December 4, it said.
"As the staff member was in home quarantine during his infectious period, they are not thought to pose any risk of infection to students and the community.
"We ask please that all in the school community maintain extra vigilant at this time. In particular, if anyone develops symptoms that might be Covid...please don't come to school, get tested, and self-isolate until you have a negative result."
He said the school continues to take all necessary precautions to keep children safe.
It comes after it was revealed last week, two staff members, one at Enner Glynn School and the other at Broadgreen Intermediate, had tested positive for the virus.
The schools were closed for a number of days last week.
And there were four new cases of Covid-19 to report in the Nelson-Tasman area yesterday. It brings the total number of active cases to 15.
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