A leading immunologist has said the current wave of Covid-19 is likely to peak within weeks as cases rise globally and across Ireland.
Luke O'Neill, a professor of immunology at Trinity College Dublin, said infections are already "trending towards a downward trajectory now" despite soaring rates again.
Ireland is in the middle of a "global wave" with the WHO showing an 8% increase in cases across the world over the past week, he explained.
This is down to the BA.2 variant which is a "sister" of Omicron albeit "much more infectious".
"It could be the most infectious virus we've seen, amazingly," he told RTE's Today with Claire Byrne programme on Tuesday.
"This BA.2 there’s nothing like it, it’s 30% more infectious than Omicron, which is already 70% more infectious than the previous one.
"Yet again the spike has changed in the virus and it sticks to your lungs much more readily and hence it spreads much more quickly.
"Secondly, the incubation time is shorter in someone who is infected so it grows more quickly in someone's body and this means that it will spread more.
"A great phrase I saw this morning is 'BA.2 is sweeping up everyone who didn’t get Omicron”. In other words it’s almost impossible now to avoid this really."
People are showing symptoms more quickly - within two days or so - compared to four days with previous variants, he said.
However, the good news is that this variant is "less lethal than flu", and this is down to vaccination
"The great news is that a wall of vaccination is holding up massively all over the world and is protecting us," Prof O'Neill said.
However, it is high risk for those who are not inoculated, he added, citing the high death rate in Hong Kong as an example of how low vaccine uptake can have devastating consequences.
People can still get "very sick" with this virus and moderate illness even if they are vaccinated, he explained.
He predicts that the peak of cases is in sight, with the current wave likely to start trending downwards next month.
"We would predict maybe early April you will see a peak in this and then we should begin to see it fall away, these waves come and go," Prof O'Neill said.
There are 137 vaccines in development for Covid, he added, with a fourth shot vital to protect against infection
His main concern is that another variant will emerge, "which might break through and be more nasty".
"There’s a risk of that for definite, every time the virus divides you might end up with another variant that could be nasty," he said.
"There’s no guarantee it gets milder as time goes by, that's a misunderstanding of how viruses work.
"There may be another variant that can cause more severe disease but the good news is we can see it coming and the booster and the fourth shot will protect against severe disease with any variant.
"We shouldn't be that fearful of it but we should be aware of it and prepare for it."
Prof O'Neill is urging people to continue wearing masks in crowded settings, like public transport, for another few weeks.
"It’s still a seasonal virus, it spreads in winter and early spring. It’s still out there and masks give protection. Even though BA.2 is more transmissible, if you do wear a mask and you do spread it, the dose will be lower," he said.
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