Schools in Northern Ireland will close from Monday, bringing them into line with their counterparts in the Republic.
Six new cases of the virus were confirmed in the north earlier, bringing the total number to 68.
A substantial number of schools across Northern Ireland had already decided to close for the rest of this week.
The North's first minister Arlene Foster says the closure could last into the summer holidays.
"The societal and economic impact of this measure will be enormous, as parents have to adjust their routine to deal with this unplanned, long-term closure.
"Our medical advice was to delay this step for as long as possible, as the closure will likely take us beyond the natural break for the summer.
"This is unprecedented."
Schools in England will close from Friday until further notice for all pupils except children of key workers and the most vulnerable, Education Secretary Gavin Williamson has said.
Mr Williamson told MPs: “I want to provide parents, students and staff with the certainty they need.
“After schools shut their gates on Friday afternoon they will remain closed until further notice.
“This will be for all children except to those of key workers and where children who are most vulnerable.”
