Ireland should be offering the AstraZeneca vaccines to younger people, according to Professor Luke O’Neill.

The National Immunisation Advisory Committee (NIAC) is meeting today to discuss ending the age restrictions on AstraZeneca and Johnson & Johnson.

Both vaccines are currently limited to people aged over 50 due to the ‘very rare’ risk of patients developing blood clots after taking them.

Last week, the Taoiseach Micheál Martin called for the age limit to be reconsidered, noting that the rise of the Delta variant among younger people has changed the balance of risk associated with them.

Meanwhile, the Tánaiste Leo Varadkar has noted that Ireland will be left with “hundreds of thousands” of unused vaccines if the age limits remain in force.

On The Pat Kenny Show this morning, Trinity Professor Luke O’Neill said there is "no question" over whether the limit should be reduced.

“The evidence, as you may remember at the start of this clotting business - remember it was always extremely rare anyway - younger people seemed at a higher risk of it, that was the suggestion – hence they say, give it to the over 60s,” he said.

“That began to become not true because it became clear age was not a predicter for clotting.

“In other words, young people have the same risk of clotting as older people - so it is across the board basically. That immediately means we should be using AstraZeneca across all age groups, there is no question now.

“Of course, we are hoping NIAC will say that and if they don’t, that means there will be doses of AstraZeneca left on the shelf unused which could be used to protect young people – especially now that Delta is here as well of course.

“So, the justification to give AstraZeneca to any age group is extremely strong now based on that and, as I say, that evidence that it was affecting people more, even though it was rare, hasn’t held up anyway.”

Mixing and matching

Professor O’Neill said NIAC must also greenlight the mixing and matching of different vaccines – noting that a new study in Spain has shown the tactic is “very safe” and delivers a “robust immune response.”

The study, published in the Lancet on Friday, involved 676 patients with those given Pfizer for their second dose and AstraZeneca for their first experiencing very high immune responses and no serious adverse events.

“There is the data,” he said. “NIAC have been saying they wanted to see more data. There is the data.

“If they don’t allow mixing and matching I would like to know why because there is the scientific evidence that it works really well and it is very safe.

'Robust immune response'

He said similar outcomes would be expected if you were to mix and match the other way around – or if you were to mix other vaccine brands.

“That would be predicted if you mix and match any combination,” he said.

“The immune system seems to like variety. If you use one vaccine first and a second type of vaccine second, it does seem to kick off even more.

“So, the prediction would be any mixing and matching will work.”

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