People in Ireland will likely receive at least one booster shot of a COVID-19 vaccine, Professor Liam Fanning says.
He said we'll have more data next year about whether boosters will be needed every winter.
Health and Government officials are already planning for the rollout of a booster campaign, which could get underway within the next two or three months.
Israel has become the first country to launch a similar campaign - and authorities have already started to give older and high-risk people a third shot.
Prof Fanning - Professor of Immunovirology at UCC - told Newstalk Breakfast it's something we'll certainly see in Ireland as well over the coming months.
He said: “Some individuals got their vaccines in the very last days of December or January… they’re already heading towards eight months vaccinated.
“We know booster shots - from the data from Pfizer and Moderna - will increase antibody levels and t-cell responses to this virus. That can only be a good thing.
“We’re all going to receive maybe one booster shot at least anyway.
"By the time we come into next March and April, we’ll have better science with regards to the longevity of the immune response we have. We may or may not need one the following year."
He said the COVID-19 vaccines are "relatively cheap medicines", but have been shown to be "wonderfully effective" in protecting people from severe disease and hospitalisation.
He noted that the upcoming booster shot campaign will likely be 'paired' with the annual flu vaccination programme.
Walk-in vaccination centres
This bank holiday weekend has seen the first walk-in vaccination centres open across the country, with the HSE saying they were "blown away" by attendance level.
Around 10,000 people are said to have gotten their first dose at one of the centres on Saturday.
Prof Fanning says the high uptake is a great news story, and the walk-in centres were perfect for a bank holiday weekend when people may have had a bit more time to attend.
He said: "It gives us some hope as well that we’ll be able to get a handle on some of these numbers we’re seeing - we’re [still] seeing up to 1,000 or more new infections per day.
"There are lots of positives to be taken from the 16-17-year-olds plus are taking up these vaccines in such high numbers.”
He said the walk-in clinics seem to have been a "resounding success", and should absolutely be kept up in the future.
However, he urged anyone who has received a vaccine at a walk-in site to cancel any other appointments they may have or be given, to "relieve some of the pressure" on the system.
Meanwhile, vaccine registration for teenagers aged 12-15 is set to open within the next two weeks.
Prof Fanning said the process of vaccinating registering that age group will be a bit more complicated as parents or guardians will need to give their consent.
He said: "I think people will want this… one [reason] is going back to school. We want to keep schools open.
"And we want to protect the wider families from picking up COVID."