Those in the 35 to 39-year-old age group can register for a Covid-19 vaccine from Sunday, the Minister for Health has confirmed.
In a post on Twitter, Stephen Donnelly said: "Delighted to announce for some of you under 40s - the registration for a Covid-19 vaccine will open to those aged 35-39 on Sunday.
"Starting with those age 39, 38 on Monday and so on."
The HSE has put the number of people aged 30-39 years to be offered vaccination at 710,000.
Earlier today, a study suggested that people who are less likely to follow news coverage about Covid-19 are more likely to be vaccine hesitant.
The Economic and Social Research Institute's (ESRI) Behavioural Research Unit found a link between a reluctance to take a vaccine and a lack of knowledge and awareness of its benefits.
The Department of Health-funded study conducted a knowledge test and survey of attitudes among a nationally representative scale sample of the Irish population in January 2021.
It found that the less people followed news coverage about Covid-19, the less likely they were to want to be inoculated.
Dr Deirdre Robertson, lead researcher on the study, said: "These results suggest that some people who are unsure about taking the Covid-19 vaccine may not know enough about it.
"The results suggest that providing factual information about how the vaccine was developed and tested, and the real-world effectiveness of the vaccines at preventing illness, may bridge this gap in knowledge."
Participants in the study completed a series of tasks designed to find out what they think about the vaccine, how much they know about it, what they see as the greatest risks and benefits, and whether they plan to take it.
A multiple choice quiz asked them questions on what they knew about the effectiveness of the jab, the development process, possible side effects and cost.
The minority of participants planning not to take the vaccine, or who were unsure, scored substantially more poorly on the quiz than the majority planning to take it.
Those planning to take the vaccine got an average score of 67%, compared with 50% for those who were unsure and just 37% for those planning not to take it.
Participants were also asked to list their thoughts about the risks and benefits of the vaccine.
Most people listed at least one risk, but there was a big difference in the listing of benefits.
Only 5% of those planning not to take the vaccine and around 50% of those who were unsure listed any benefit at all.
This compared with 91% of people planning to take it.
Professor Pete Lunn, head of the Behavioural Research Unit, said: "Since we collected this data, the numbers wanting to take the vaccine have risen steadily, perhaps reflecting improved knowledge and recognition of the benefits that the vaccine brings.
"But the study shows that a minority of the population do not follow the news about Covid-19 and may take longer to realise how effective and safe the vaccines are."
The working paper, A Lack of Perceived Benefits and a Gap in Knowledge Distinguish the Vaccine Hesitant from Vaccine Accepting during the Covid-19 Pandemic, will be published today.
Meanwhile, the Secretary General of the Irish Pharmacy Union has said vaccine pre-bookings have been very strong in some pharmacies, while others have found they are getting more inquiries from those under 50 who are anxious to receive the jab.
Speaking on RTE's Morning Ireland, Darragh O'Loughlin said that up to 800 pharmacies are receiving delivery of the one shot Johnson & Johnson vaccine.
It will be given to those over 50, who have not yet received the jab.
He said that people will have to book their appointment and it is unlikely that pharmacists will be able to take walk-ins because each vial contains five doses and must be used within three hours of opening.
Mr O'Loughlin said there is a good spread of pharmacists providing the vaccine, from the middle of Dublin city to small towns and villages across the country, and it will bring the vaccine into small communities so people can get it without travelling.
He said the vaccines will be stored in pharmaceutical grade fridges so storage will not be a problem.