The new Omicron XE variant may be 10-20% more transmissible than previous variants, research from the UK suggests.
The only case of the new variant confirmed in the Republic so far was a travel-associated case in February 2022, according to the Department of Health.
In the UK, around 1,000 Omicron XE cases have been identified.
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Speaking on RTE's Morning Ireland, Professor of Immunology at Trinity College Kingston Mills said sequencing data suggests the new variant is more transmissible than BA.2.
"In the UK they have had over 1,000 cases (of the XE variant) so they are sequencing more," he said.
"There is a suggestion that it may be more transmissible than BA.2 by about 10-20%."
Professor Mills said while the new variant is "reasonably mild in healthy people" there are "two big worries".
"One is the older and vulnerable people getting infected because it can still be a severe disease, especially if they haven't been vaccinated," he said.
"And the second worry is other variants arising such as this XE. Now it mightn't be any worse than BA.2 or Omicron but in India right now there is a series of new variants emerging.
"In India, the Covid-19 pandemic is out of control again and there have been 6 million cases there so far in April."
Professor Mills said we have to monitor new variants and "not get complacent".
"(India) has not been as good at vaccinations as other countries, we have to watch that carefully and not get complacent about the fact that the pandemic is complete," he said.
"I am not trying to be scaremongering but we need to be prepared if we do see a variant that completely evades immunity with the vaccines."
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