More than 30,000 Covid-19 tests have been carried out since the outbreak began here
Healthcare workers are being prioritised for testing because the sector makes up a quarter of all cases in Ireland.
Dr Cillian de Gascun, chairman of the Coronavirus Expert Advisory Group, says the change in criteria for testing is working.
"Of interest to us in light of the changed case definition last week, you might remember the positivity rate up to last week was 6%, and the positivity rate of those samples that have been tested in the last week is up to 15%.
"That's really one of the things we were trying to achieve by changing the case definition to ensure we were testing the right people.
"Early signs are that we've managed to achieve that to an extent."
Meanwhile an Irish company is to receive €10m from the EU Commission to develop a rapid test for Covid-19.
Hibergene Diagnostics from Dublin is one of 17 companies in Europe to benefit from an overall EU grant of €48.5m.
