Cork experts in the areas of biology and pharmacy have said that there is “no evidence” that the variants of the virus in Ireland would make the Pfizer vaccine currently being administered any less effective.
Principal investigator and special lecturer in advanced therapies at University College Cork’s (UCC) School of Pharmacy, Dr Piotr Kowalski, said that the only evidence seen so far is that mutations of the virus have made it more transmissible.
“Right now with the current mutation we have there is no evidence that they are sufficient to compromise the efficacy of the vaccine. The only evidence we have and that we are seeing is that these mutations make the virus spread faster, but no evidence mutations would lead to a virus comprising the vaccine efficacy,” he said.
Dr Kowalski said, however, that there is a risk that if more mutation accumulates in the spike protein and if we allow the virus to spread with this mutation, that “these vaccines may become less effective because the antibodies that the vaccines will produce will stop recognising as effectively this spike protein”.
“So we really need to contain the strains and the spread of those strains and prevent them from accumulating more mutations,” he said.
Senior lecturer in biochemistry at UCC, Dr Anne Moore, explained how variants of the virus have mutations in different proteins found in the virus and said that concern, when it comes to the vaccine, lies with mutations of the spike protein, a protein responsible for latching on to the cells and allowing the virus to infect those cells.
“Some of the mutations are in the key part of the spike protein that is involved in how strongly that protein binds to the receptor on the cells and that mutation allows the virus to attach better onto the cells and because of that, if the virus has a better possibility of getting into a cell you’re going to have more virus getting in,” she said.
She said, however, that Pfizer has produced data showing that “in at least some of their immunised individuals it still recognises the spike protein despite the fact it has some mutations on it”.
Dr Anne Moore explained how certain variants of the virus become more dominant and spread more easily from one person to the next.
“It’s evolution, if you have a virus that has a number of mutations that makes it more fit to go from person to person, that is the one that will take over and become more dominant.
The sum total of mutations that happened in the UK variant has made it more fit and you'll have higher virus loads or amounts in peoples’ airways which means you are significantly increasing the possibility of a virus particles going from one person to the other so you're increasing the chances of spreading the virus because there's more there to start with.
She said that millions of variants have been found by people carrying out genome sequencing of the virus but that certain variants are fitter, surviving longer and being spread more quickly by people going from one country to another.
“These variants are much more transmissible and it is frightening,” she said.
Dr Moore said that classically, coronaviruses are not seen as mutating very quickly, while HIV mutates within an hour and the flu mutates over a season, but that “if there is the possibility of a mutated virus surviving better than other ones then it will”.
She said that mutations can occur in people who are ill with the virus and who do not have a strong enough immune system to fight it off, giving the virus “the perfect housing conditions” to to start changing but to still survive.
Dr Moore said that we must make sure people are vaccinated in “a very timely manner” and that we do not have a mediocre vaccine-induced immune response in some people, highlighting the importance for people to be “fully vaccinated”.