The Government expects a recommendation from medical experts in the coming days on spacing out the intervals between doses of the Pfizer/BioNtech and Moderna Covid-19 vaccines, the Minister for Health has said.
Stephen Donnelly said they are asking the question whether it would be worth extending the gap between the first and second doses of the vaccine to eight or 12 weeks.
Speaking on RTÉ's This Week he said the data in Ireland and internationally shows that even the first dose is showing "incredible positive signs" in the reduction of cases and hospitalisations.
Mr Donnelly said while there is no memo being written at the moment on spacing out vaccine intervals, public health officials and the vaccine task force are looking at it.
He said he has sought the advice of Deputy Chief Medical Officer Dr Ronan Glynn who will be discussing it with NIAC.
"I have no doubt he is already talking to NIAC," Mr Donnelly said, adding that he will be sitting down with Dr Glynn in the coming days to look at the various options.
The Minister for Health has also said the Covid-19 vaccination programme remains aged-based, while defending his "probing" of any possible changes to it.
Mr Donnelly said he asked officials in the Department of Health to examine the case of vaccinating younger age groups earlier than others, saying it was based on the National Immunisation Advisory Council's orignial strategy.
He said it was based on the original NIAC pioritisation which included this option for younger people being vaccinated as there is more transmission among this age group.
"What the original NIAC strategy had said was that if the data on transmissibility in regard to the vaccines was strong enough then it should be something to be considered," Mr Donnelly said.
He said when he put the question to the Deputy CMO earlier this week on this, he was told the data on transmissibility is still emerging and is not at a place yet that would warrant a change.
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Minister Donnelly said they are constantly probing the vaccine programme to see how quickly the spread of the virus can be suppressed.
"All we were doing was looking at an existing NIAC position," he said.
Mr Donnelly said there is one age cohort of 18 to 24 from the data where they consistently see a higher rate of transmission.
"Given we are all looking at ways of improving the vaccine programme, I thought it was timely to ask for a review given NIAC had flagged it some time ago," he said.
The Minister said he did not tell his Government colleagues about this assessment he had asked for, as he believes all he was doing was asking a question.
He also said he does not think anyone should be confused by it as they are not making any change to the age cohorts within the vaccination programme.
"We simply asked the question."
He added that he thinks it is expected of him as Minister for Health to be asking those type of questions.
Yesterday, a number of Opposition politicians criticised Mr Donnelly for causing "utter confusion" about the vaccine roll-out plan.
Ireland in 'significantly better place'
Mr Donnelly has said Ireland is in a "significantly better place" than was anticipated four weeks ago and if it continues like this, it puts Ireland in a very positive position for the summer.
"What that means is we can look at the full list that was set out two or three weeks ago.... adding that "it puts us in a very positive position for the conversation about May, June and July".
He said if the Government plan continues to work and bend down the curve, there can be a very encouraging conversation about summer.
Mr Donnelly said this week and last week the R number has remained below 1 so cases are steadily decreasing.
He explained that under consideration for the start of May is the full reopening of "construction, non-essential retail, personal services, museums, libraries, religious services and so forth".
He said no decisions have been made along the lines of hospitality and outdoor pubs yet.
Speaking about variants, Mr Donnelly said the risks associated with the Indian variant will be looked at this week but added that to date that there has been no discussion about any other countries being added to the mandatory hotel quarantine list.
Regarding mandatory home quarantine for those who are fully vaccinated who arrive into Ireland, he said it is about getting the right balance in place.
Mr Donnelly also spoke about an EU digital certificate in the coming months which he said would be an international verification mechanism.
He said his hope will be that all of the EU and others sign up to allow those who are vaccinated freely.