The number of weekly Covid outbreaks recorded in schools doubled again last week, according to latest data from the Health Protection Surveillance Centre (HPSC).
There were 46 outbreaks in the week-ending October 17 - last Saturday - compared with 25 the previous week.
The figures for the week-ending October 10 were, itself, a doubling of 12, 13, 11 and 12 in each of the preceding four weeks.
It brings the total since term began to 119, out of 4,000 primary and post-primary schools.
Although the number is relatively low and schools are not seen as hubs for transmission of the disease, the figure reflects how the increasing level of infection in the community is seeping into education settings.
The spread has added to pressures on principals, teachers and other school staff, compounded by delays in contact tracing and testing because the system was overwhelmed.
Post-primary schools are much more likely to experience an outbreak than primary schools, according to information provided to Aontú leader and TD Peadar Tóibín
Data released by the HSE in response to a parliamentary question, shows that, up to October 14, mass testing had been undertaken at 102 post-primary schools - out of a total of about 730.
By comparison, mass testing had been conducted at 184 primary schools, out of a total of about 3,100 mainstream primary schools.
Over the same period, testing had also been conducted at 84 childcare facilities and 14 special education settings.
Up to that date, the mass testing detected 125 additional cases, across 47 schools - 20 individuals are over 18 and the remaining 105 were under 18.
Some 56pc (214)of the settings were in the East classified by Public Health department - with 8pc each in the Midlands and North-East, 7pc each in the West and Mid-West, 6pc each in the North -West and South and 3pc in the South-East.
Mr Tóibín criticised delays in testing that have been experienced and said the regime needed urgent improvement.
“My constituents are telling me they were waiting up to five days or a week for their child to be tested after being told to self-isolate.
“Delays in testing have a knock-on effect on others, a child waiting a week for a test means he or she will fall behind in their studies, it means that if they are positive, the virus has had plenty of time to spread to others who haven't been told to self-isolate, it also means that a parent or family member has to take time off work to care for the child.
“If we are to keep schools open then we need intense testing and tracing, and we cannot afford delays."
The strain on schools was evident earlier this week when some took a decision to close because they couldn’t get updated information from public health officials.
Where an outbreak – two cases or more - occurs in a school, the HPSC says transmission of Covid-19 within the school has not necessarily been established.
Health chiefs say it is more likely that children, or staff, bring infection in from outside.
Confirmation of a Covid infection in an educational setting triggers a Public Health Risk Assessment (PHRA) which determines what action, such as identifying and contacting close contacts, and testing, is required.
Public Health officials also vested with the task of contact tracing, but some principals have been doing that themselves in a bid to speed things up.
Earlier this week, Education Minister Norma Foley said 10,513 students and staff had been swabbed arising from a confirmed case in a school.
This has resulted in the detection of 246 additional cases, a positive detection rate of 2pc, compared with over 7pc in the wider community.
Sixth year is an incredibly difficult year for students and their families every year. The Leaving Cert really is one of the most difficult exams a student will ever take. The challenge comes from having to study six to seven large courses which have little or no continuous assessment, so the entire focus is on the June exams.