A professor of immunology from Maynooth University has predicted some variants will continue to cause infections in those who have been vaccinated.
Professor Paul Moynagh has told Newstalk that herd immunity “could be very difficult to achieve” due to the emergence of new variants of Covid-19 and the percentage of unvaccinated people, including children.
The immunology expert said “we wouldn’t be able to get to 90%” vaccination levels, which he believes is required for herd immunity, and also questioned whether the benefits of vaccination for children outweighed the risks, given the very rare occurrence of severe Covid-19 disease in minors.
“The EMA’s already approved Pfizer for the use in children from the age of 12 to 15, that’s currently under consideration by NIAC,” Moynagh explained.
“So when you look at the use of vaccines in various age groups, it’s important to look at the benefit to risk ratio.
“So far when you’ve applied that to all age groups in the adult cohorts, the benefits outweigh the risks.
“With children, that benefit to risk ratio gets smaller – with younger age groups… children are reasonably resistant to the virus, and especially in terms of developing severe COVID, although it can happen in some cases.
“The other slight concern is that, in some cases, it’s been observed that with the RNA vaccines – including the Pfizer vaccine – there is a condition known as myocarditis which is inflammation of cardiac or heart muscle.
“That’s an incidence of about one in 20,000, so that has created some concern… so that narrows that gap in terms of the benefit to risk.
“If we’re looking at a situation where we can to try to reach herd immunity, certainly you’d have to vaccinate children.
“Now is herd immunity achievable, and I think that’s the question now.
“We’re talking about approving a vaccine for 12 to 15-years-olds, but again we wouldn’t be able to get to 90%.
“The other consideration is the fact that some of these variants can… cause infection to those that have been vaccinated.
“I think we could be looking at a situation where it’s going to be very difficult to achieve herd immunity.
“I think, globally over the coming months and years, we’re probably going to be looking at a situation where everybody will end up either being vaccinated, or actually infected by the virus or in some cases both”.
Moynagh also called for more data in order to assess whether a winter wave could see significant numbers of unvaccinated children being hospitalised with severe Covid-19 infections.