The first cases of a new Covid-19 variant of concern have been detected in the Republic.  Chief medical officer Dr Tony Holohan said Two cases of BA.4, a sublineage of the currently dominant Omicron were detected earlier this month  For more on this Ciara spoke to Professor of Experimental Immunology at Trinity College Dublin, Kingston Mills. Listen and subscribe to Newstalk Breakfast on Apple Podcasts or Spotify.     Download, listen and subscribe on the Newstalk App.    You can also listen to Newstalk live on newstalk.com or on Alexa, by adding the Newstalk skill and asking: 'Alexa, play Newstalk'.