Sir Jeffrey Donaldson has encouraged the public to take up the offer of the booster vaccine, after receiving his jab at the Ulster Hospital on Monday.
The DUP leader said the emergence of the Omicron variant was a reminder of the threat still posed by Covid-19.
Health Minister Robin Swann told the Assembly on Monday the variant is likely already present in Northern Ireland.
The Omicron variant, which has been labelled a “concern” by the World Health Organisation, has been detected in England and Scotland, and was linked to travel in southern Africa.
No cases have yet been notified in Northern Ireland or the Irish Republic.
Speaking after receiving his booster jab, Sir Jeffrey said the booster programme is the “single most effective tool” in reducing the pressure on the health service.
He added that in evidence given to Executive ministers it highlighted the booster jab would reduce hospitalisations by at least 15%.
“I would encourage everyone eligible to take up their booster,” stated Sir Jeffrey.
“The Covid vaccines not only help protect you, but help reduce the spread of the virus and help protect others.
“It will be important that the booster programme is ramped up over coming weeks but alongside that it is important we all continue with the simple, common sense steps which can reduce spread of this virus.”