The National Public Health Emergency Team (NPHET) is currently reviewing whether or not rules for students who are close contacts can be eased by the end of September.
With over 1,000 pupils being sent home every week since the return to school, many have been calling for the relaxation.
However, representatives of the Fórsa trade union have today said it is "far too early" to ease the existing test and tracing system in schools.
They have called for things to remain as they are with close contacts isolating at home until they produce a negative test until there is 'clear data' that shows transmission of the virus reducing to the levels seen in 2020.
Plans being considered by NPHET would allow unvaccinated children who are close contacts of a confirmed Covid-19 case to remain in school from the end of September if they are not showing symptoms.
The changes were being considered because the existing rules being followed are resulting in around 1,200 children being sent home to restrict their movements each day.
Andy Pike, head of education at Fórsa, says staff working in schools across the country believe that the highly transmissible Delta variant could pose additional challenges as the year goes on.
"Covid positivity rates immediately prior to the 2021 school reopening were alarmingly high," Mr. Pike explained.
"Data from the first two weeks of the new term appear to show a reduction to a level of 4%, which is comparable to figures for the last school year.
"But the data is incomplete, and we need to exercise caution prior to and during any relaxation of the existing safety measures."
The HSE has said the rise in positivity rates may be as a result of the increased testing capacity since the return to school, but Mr. Pike insisted; "It is too early to draw any conclusions on relaxing protections.
"We will need to be certain that the measures in place will effectively prevent wide-scale transmission before deciding that they are no longer needed.
"We could not support such a policy until there is clear evidence that this approach of relaxation would not increase transmission.
"We acknowledge that working parents and employers are experiencing difficulties because of the large number of students currently required to restrict their movements, but policy must be based on clinical evidence rather than business interests."
