Cavan and Monaghan saw 24 new cases of Covid-19 yesterday.
The latest figures from the Department of Health show 15 of those were in Monaghan, with nine in Cavan.
Both counties have seen an increasing number of confirmed Covid-19 cases over the past two weeks.
The latest data from the Health Protection and Surveillance Centre - up to midnight on Saturday - shows an incidence rate per 100,000 of 68.4 in Monaghan and 35.4 in Cavan.
This compares with 178.4 in Donegal - the highest in the country.
Meanwhile, the acting Chief Medical Officer has warned the situation with Covid-19 will continue deteriorate unless everyone plays their part to stop its spread.
Dr Ronan Glynn says there's 'no room left for complacency' and has appealed for people to reduce their contacts over the coming week.
430 more people have tested positive for coronavirus -- with yesterday's figure the highest since April. 212 were in Dublin and 23 in Donegal, but doctors have voiced concerns about Cork, where there were 54 cases, and Galway with 23.
