As NPHET meets to consider whether more restrictions are needed, People Before Profit TD Paul Murphy said the schools are now the number one location where we have outbreaks of Covid.
"So much for the mantra that's schools are safe,” he told Newstalk this morning.
"Primary schools still, really disgracefully, do not have the HEPA filters that they need to have.
"There's only three days left and... in terms of Omicron, the data coming out - we may wish it was not so - but the data coming out is extremely concerning about how transmissible Omicron is.
"If you look at the figures in Britain, at the moment it appears to be doubling the case numbers every two days.
"It is here, it's increasing at a very rapid rate here.
He added: "And at those numbers - even if it was the case that there was a lower level of hospitalisation associated with it - just the sheer scale of the numbers of cases that you're talking about, in a couple of weeks' time it would overwhelm our hospitals".
Fine Gael senator Jerry Buttimer also called on Education Minister Norma Foley to close schools this weekend.
“Covid is running riot in our primary schools,” Mr Buttimer told the Seanad on Wednesday.
“Whether it's through close contacts or actual physical cases, absenteeism in primary schools is at an all-time high,” he said.
“I know of one school, where in a population of less than 700, there are 100 people absent from the school.
Mr Buttimer said he was asking the minister to close the schools early “in the interest of public health”.
“We all know there will be intergenerational mixing over Christmas and to stop and to limit the spread of Covid, I'm asking the minister to close up primary schools on Friday to allow for a planned reopening in January, [and] to prevent the spread of Covid-19.”
He added: “Our primary schools are probably the one place where we have the most unvaccinated people, young people in particular, gathering at any one time.”
“They are wearing masks but I would ask and I really am appealing to the Minister of Education to close up primary schools on Friday as a public health measure to support the good work being done by Government and the HSE.”
On Tuesday, the Department of Education said it had no plans to alter the Christmas school break or to close early.
"There is no evidence to suggest that extending school holidays has a public health rationale," a spokesman for the department said.
Labour's education spokesperson Aodhán Ó Ríordáin says closing school early would have a knock-on effect.
"I think it's a shame we're having this debate, and I would agree that if Government had done more in terms of the education system over the last number of months we'd be in a better position to keep them open.
"It's not a kind of a debate where you can come down 100% on either side.
"If they were to be closed because NPHET said they should close, then we'd have no difficulty with that.
"The problem is [if] you close primary schools, it follows down that childcare needs to close.
"You do that and then you have a lot of families who are not going to be able to function Monday, Tuesday, Wednesday next week."
And he says this could make it harder for them to re-open in the new year.
"Then it follows on it's going to be very difficult to open them up again in January.
"It's probably the biggest decision that they'd have to make.
"The numbers are difficult now, as inevitably it seems to be the case in January when they worsen, it would be extremely difficult to open them up again".