It is not realistic for the Government to believe that close to half the Irish population will be vaccinated by the end of April, according to Professor Tomás Ryan.
The assistant professor at Trinity College’s School of Biochemistry and Immunology told Newstalk Breakfast that even with the most ambitious targets set by the Taoiseach, the April goal was not realistic.
His comments come after Taoiseach Micheál Martin announced the Government aim to have administered first vaccine doses to 40 per cent of people over the age of 18 by the end of April, 64 per cent by the end of May and up to 82 per cent of adults by the end of June.
Prof Ryan said that half the population might realistically have had a single dose of the vaccine by the end of June.
Having half the population vaccinated by April could present “a very risky situation” which would be ideal for variants to emerge that were vaccine resistant, he added.
While Covid-19 was “on its way out”, it could be some time before a widespread vaccination programme was completed, Prof Ryan said.
“If we come out of this lockdown and we don't have low enough case numbers, we can easily be heading quickly towards a fourth wave if - with this new variant - there's too much of it in the population.”
However, Prof Ryan acknowledged that some indicators of the pandemic were improving, but not at as fast a rate as some would like.
The 14-day average of Covid-19 cases was looking good in places like Cork, Kerry, Kilkenny and other counties, but not declining in Dublin, Galway and Offaly.
“This lockdown is a longer lockdown than any of us would have liked - that's almost certainly due to the B117 variant which is now dominant in the population - which means it is going to be a slightly longer lockdown, or the alternative is we could find ways of going harder,” he said.
On Wednesday, the Minister for Health said that Ireland has ordered enough Covid-19 vaccines to fully vaccinate its population of some five million people twice over.
Stephen Donnelly said the State has total orders in place for 18.5 million doses of Covid-19 vaccines — enough to vaccinate 10.3 million people.