There have been ‘remarkably low’ COVID-19 positivity rates in schools where mass testing has been carried out, the HSE’s Dr Colm Henry says.
He says there’s ‘no evidence’ that schools are major incubators of the virus.
Hundreds of thousands of children and teenagers have been back at school for several weeks, with the remaining secondary school students set to return after the Easter break.
Mass testing is carried out in a school when a coronavirus case is identified, to see if the virus has been transmitted to other students and teachers.
The most recent HSE schools report showed there were 171 cases detected when over 6,680 students were tested across 218 schools - a positivity rate of 2.6%.
24 school outbreaks were reported in the week up to 20th March, although the HPSC says that does not necessarily mean the virus was transmitted within the school.
On The Pat Kenny Show, Dr Henry - the HSE’s chief clinical officer - said they can never say for certain that they’ve picked up every case in schools.
However, he said: “If you talk to public health experts and look at the facts from our testing… there’s no evidence that schools are great incubators of COVID-19.
“Rather than being threats to the community, it’s clear that community transmission is a much greater threat to schools.
“Even since the schools reopened, after we test those index cases and mass testing is carried out… the level of positivity remains remarkably low at primary and post-primary level.
“This clearly infers to us that the disease is largely brought into schools, rather than created within schools.”
Dr Henry said officials are now looking at a pilot scheme of antigen testing in secondary schools and universities.
However, he said concerns remain around the sensitivity of the rapid tests - and stressed that they wouldn’t replace existing measures.
He said: “We already deploy antigen testing for our hospitals and in outbreak settings, where we know its sensitivity is much stronger. But we also know it's very weak in cases where people are asymptomatic.
“I’m not doubting the potential value of antigen testing, particularly in outbreaks… I’m saying that as an assurance to people that a negative test means negative by itself it doesn’t stand up.
“We have more than enough PCR testing for the settings that really need testing.”
Last week also saw five pop-up, walk-in testing centres open in Dublin and Offaly.
Officials want to see if they can detect more COVID-19 cases in areas where the virus remains stubbornly high.
Dr Henry said the centres have seen a 'big take-up', with 7,500 tests in recent days showing a positivity rate of around 2-3%.
He said: “This is part of a menu of options that allow us to identify cases.
“From here on out, we envisage these would be highly mobile - and we’ll change the location based on the advice of public health departments.”