THERE have been more than 300 fresh cases of Covid-19 in schools since pupils returned to classes last month.
Some re-opened schools have had to close again temporarily while there has been a rise in the number of `clusters' of six or more cases.
Pre-school and P1-3 pupils re-started full-time face-to-face teaching on March 8.
P4-7 and older exam year post-primary students went back two weeks later.
All pupils are due to resume classroom learning after the Easter holiday.
The Public Health Agency has been compiling school-based figures in its Weekly Epidemiological Bulletin.
In the week ending March 28, it reported that there had been 5,500 total cases in schools dating back to the start of the pandemic.
This was higher than the figure of 5,198 reported in the week ending March 7, the day before the first children returned.
A total of 889 schools have been affected - almost 60 per cent of all Northern Ireland schools.
There has been 3,518 cases among pupils - a rise of almost 200 since the re-start. Among teaching and non-teaching staff, there have been 1,982 cases - up from 1,876 before children returned.
In that same period, the number of clusters of six or more reported has increased from 212 to 227.
The number of cases in post-primary schools reported in the PHA's March 28 bulletin was 32 higher than the number reported on March 21, the day before Years 12-14 returned.
There has now been 2,115 cases in post-primary schools among pupils, since the start of the pandemic.
The figures for special and pre-schools are now 101 and 73.
The highest proportion of incidents (71 per cent) have been reported in Belfast and Derry and Strabane council areas.
