Minister for Health Stephen Donnelly has announced that those in their 40s will be able to access a Covid-19 booster vaccine dose from this Sunday 19 December – more than a week earlier than previously planned.
Booster vaccinations for those aged 40-49 had originally been slated to begin from 27 December.
In a statement this evening, Mr Donnelly announced that this has been brought forward to this Sunday, available through a mixture of booked appointments and walk-in clinics.
Booster doses will be available at vaccination centres, as well as through GPs and pharmacies.
The move comes as a further 3,628 new cases of Covid-19 were reported by the Department of Health this evening.
There are 420 people in hospital who have tested positive for Covid-19, down 23 from yesterday.
It represents the lowest figure in almost nine weeks, since 16 October, when there were 406 people in hospital with the coronavirus.
105 of these are receiving treatment in intensive care units, down three from yesterday.
The Department of Health estimates that 35% of cases are now due to the Omicron variant.
In Northern Ireland a further three patients who had previously tested positive for Covid-19 have died.
Another 1,887 confirmed cases of the virus were also notified by the Department of Health.
There were 312 Covid positive patients in hospital this morning, of whom 34 were in intensive care.
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Meanwhile, the head of the HSE has said the "strongest and most pre-emptive strike" they can make in relation to the Omicron variant of Covid-19 is the vaccine booster programme, and getting more people boosted in a quicker period of time.
Speaking on RTÉ's Morning Ireland, Health Service Executive CEO Paul Reid said the number of people in hospital with Covid-19 is "still a very high base for which we head into all of the indications of what Omicron will bring."
The HSE is looking at scaling up ICU capacity and also looking at how to move into a surge if required, he added.
He said hospitals took the right actions to dial down on non urgent care when they saw the surge in the Delta wave recently, but said elective care is now happening again in most hospitals over last two to three weeks.
The number of healthcare workers who are not at work due to Covid-related sickness, has "had a severe impact", but Mr Reid said this figure has decreased from around 5,800 to just over 5,000, with a "significant proportion" of those affected being frontline workers.