Principal David Oliver told Hawke's Bay Today the case was confirmed late on Wednesday.
It was not added to yesterday's active case tally, but will be today.
"This student was already isolating and there were no new close contacts resulting from this case."
The school had 87 students identified as close contacts, who were contacted by the school via email with instructions of what the next steps were, as advised by the Ministry of Health.
As a result of the active cases, the school decided to close for the remainder of this week.
"From February 16 to February 18 our students will be learning from home with an online timetable.
"All staff have been working at school, including several students requiring supervision."
Oliver said the decision to close the school was to allow for further contact tracing and to prepare for the return of those students on Monday, February 21.
All staff working at the school are vaccinated, he said.
"We are continuing to work with the Ministry of Health and the Ministry of Education around supporting our school community and to ensuring that student learning can continue to take place, both online and at school."
In Hawke's Bay 6489 5 to 11 year-olds are partially vaccinated, that's 36.6 per cent of the eligible population of 17,749.
Meanwhile, there were delays in obtaining free Covid-19 tests in Napier on Thursday.
The Hawke's Bay DHB Facebook noted that Napier's Whitmore Park 'no appointment' testing site was not open, but reopens on Friday.
A DHB spokeswoman said Whitmore Park was administering the Covid vaccination on Thursday, and therefore couldn't undertake tests at the same time.
Napier residents phoning to book tests via the clinic next to The Doctor's Napier were met with an automatic message advising tests were in "extremely high demand" and to call back later or book online.
The automatic message also said there would be a 24 or 48 hour delay in getting a Covid test.