Ryan Baird has been formerly ruled out of Ireland's remaining Six Nations games with Italy and France.
The Leinster lock suffered an adductor injury in last weekend's Guinness PRO14 victory away to Benetton.
His place in the Ireland squad for the last two rounds of Six Nations goes instead to Connacht second-row Ultan Dillane.
Jordan Larmour had already been ruled out Ireland's entire autumn campaign with a dislocated shoulder that requires surgery.
The IRFU have confirmed that Munster duo Peter O'Mahony and Chris Farrell have suffered collateral damage of the recent COVID-19 cases at their province. Both were deemed close contacts of a positive case at Munster and are completing a period of isolation prior to joining the Ireland squad on Monday.
Andy Farrell's side are due to play Italy at the Aviva Stadium on October 24, before a Hallowe'en showdown with France in Paris.
As revealed by Leinster earlier this week, Jonathan Sexton and Andrew Porter's respective hamstring injuries, and Ronan Kelleher's quad problem will all be attended to by the Ireland medical team this week.
Connacht pair Finlay Bealham and Dave Heffernan are progressing though the return to play protocols.
All players and management produced negative PCR tests on Monday ahead of entering national camp.
Both Six Nations opponents have endured problems of their own ahead of the remaining games.
Italy's scrum-half Stephen Varney is isolating after testing positive for COVID-19.
While France will be without Bordeaux duo Matthieu Jalibert (out-half) and Cameron Woki (back-row), as they've both picked up injuries. They'll be replaced by Pau forward Baptiste Pesenti and Toulon winger Gabin Villière.
Ireland squad (v Italy & France):
Bundee Aki (Connacht/Galwegians) 26 caps
Ross Byrne (Leinster/UCD) 6 caps
Jack Carty (Connacht/Buccaneers) 10 caps
Andrew Conway (Munster/Garryowen) 21 caps
Shane Daly (Munster/Cork Con) uncapped
Chris Farrell (Munster/Young Munster) 9 caps
Jamison Gibson Park (Leinster) uncapped
Robbie Henshaw (Leinster/Buccaneers) 43 caps
Hugo Keenan (Leinster/UCD) uncapped
Kieran Marmion (Connacht/Corinthians) 27 caps
Stuart McCloskey (Ulster/Bangor) 3 caps
Conor Murray (Munster/Garryowen) 81 caps
Garry Ringrose (Leinster/UCD) 29 caps
Jonathan Sexton (Leinster/St Mary’s College) 91 caps CAPTAIN
Jacob Stockdale (Ulster/Lurgan) 28 caps
Finlay Bealham (Connacht/Corinthians) 9 caps
Tadhg Beirne (Munster/Lansdowne) 13 caps
Ed Byrne (Leinster/UCD) uncapped
Will Connors (Leinster/UCD) uncapped
Jack Conan (Leinster/Old Belvedere) 17 caps
Ultan Dillane (Connacht/Corinthians) 15 caps
Caelan Doris (Leinster/UCD) 2 caps
Cian Healy (Leinster/Clontarf) 98 caps
Dave Heffernan (Connacht/Buccaneers) 1 cap
Iain Henderson (Ulster/Academy) 55 caps
Rob Herring (Ulster/Ballynahinch) 11 caps
Ronan Kelleher (Leinster/Lansdowne) 3 caps
Peter O’Mahony (Munster/Cork Constitution) 67 caps
Andrew Porter (Leinster/UCD) 26 caps
Quinn Roux (Connacht/Galwegians) 12 caps
James Ryan (Leinster/UCD) 26 caps
John Ryan (Munster/Cork Constitution) 21 caps
CJ Stander (Munster/Shannon) 41 caps
Josh van der Flier (Leinster/UCD) 26 caps