Kildare accounts for 18 of the 85 new coronavirus cases confirmed on Thursday evening by the Department of Health.
The jump is the biggest daily increase since May and has experts fearing that the virus could soon spiral out of control.
11 of the cases were in Dublin which has been the epicentre of Ireland's pandemic since it began.
Counties that had been seeing much fewer cases however have also seen a rise in the latest spike.
Clare's figures rose by 9 having previously been weeks without a new case.
Limerick, again regarded as nearly coronavirus free, saw a burst of seven new cases while Meath rose by four.
The other 46 cases have been spread amongst other counties while some may not have been given an exact location just yet.
It is understood that between 30-40 of the new cases were related to outbreaks at a dogfood factory in Kildare.
This outbreak is also associated with clusters in two direct provision centres where some of the workers are living.
Dr Ronan Glynn said on Friday morning that many of the cases are related to relatives visiting each other in different parts of the country.
