The World Health Organisation says there's a 'real chance' the Delta variant will become the dominant strain of Covid-19 in Ireland.
It comes as the chief medical officer says there's been a 'concerning increase' in cases of the strain here.
About a fifth of infections in the past week involved this variant, which is more transmissible.
A total of 284 new cases of Covid-19 were confirmed here yesterday.
Dr David Nabarro, from the WHO, says the Delta variant is very concerning: