The coronavirus death and hospitalisation rates will “plummet” when the top four priority groups are vaccinated, according to Trinity Professor Luke O’Neill.

The Government has originally hoped to offer a vaccine to every adult in Ireland by September; however ongoing supply issues will likely delay the timeline.

The Minister for Health has also predicted that everyone over the age of 70 will have been offered their first dose by next month.

Under the current vaccine priority plan, the top four priority groups are:

• Residents and staff in nursing homes
• Frontline health workers
• People aged over 70
• Other health workers.

On The Pat Kenny Show this morning, Trinity Professor Luke O’Neill said two new studies in the US and the UK suggest that vaccinating even a small portion of society can have a big effect on the overall virus figures.

“There were two huge papers on this over the weekend and they are really good actually because it is modellers and they are saying, ‘look, if we vaccinate the following priority groups what will that do to the death rate or the level of illness?’ – and again it looks really good.

“So, in the US, if you vaccinate 40% of the US population, you will see a four-fold decrease in new infections, an 85% decrease in hospital ICU admissions and an 87% decrease in the death rate.

“That is with 40% of the population being vaccinated. Then they said what if you only vaccinate 20%? And they found a 60% decrease in hospitalisations and a 64% decrease in deaths.

“Now that is based on modelling, obviously, because they are projecting it, but there is the evidence.

“We are getting more and more evidence that as we begin to vaccinate through these groups all these metrics will begin to plummet.”

He said the important thing about the studies is that all the modellers involved were in agreement.

“Obviously, this is based on mathematics to some extent but they are all now agreeing with the same kind of ballpark figures in terms of these numbers decreasing,” he said.

A woman walks past a boarded-up shop on Dublin's Grafton Street, 04-07-2020. Image: Brian Lawless/PA Wire/PA Images

He said the expected drop-off in deaths and hospitalisations will open up a “big debate” on the restrictions moving forward.

“If they vaccinate the top four priority groups in Ireland say, then we are going to see those metrics plummet,” he said.

“Then the Government will then have to begin to decide what to do with that.

“The trouble is, there will still be people not vaccinated in the community obviously so they will be worried about that group clearly and we will still have restrictions.

“In fact, even in the big study in the US there, when they get to 40% that means 60% are not vaccinated. So again, you will still be wearing masks and distancing and so on.

“Whether you begin to loosen things up quickly or slowly that will be the next big debate.

“You can imagine the pressure will be great. If our death rate plummets by 95% and the hopitalisation rate goes way down - and we can project that for April, May June time - then they will have to say, ‘look, we have got to relax things.’

“It is just a question of which things they relax first I suppose.”

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