New Ross in Co Wexford has the highest coronavirus incidence rate on the island of Ireland, with areas in Monaghan, Donegal, Antrim, Fermanagh, Armagh and Kerry also seeing a marked increase in infections.
Confirmed Covid-19 case numbers from electoral areas in the South and postcode areas in the North give an indication of how the disease is spreading in different communities.
Both sets of statistics use the incidence rate of infection per 100,000 of population, giving a better understanding of the spread than straight case numbers.
Currently, the New Ross local electoral area has the highest infection rate in Ireland. The area saw 998.6 cases per 100,000 recorded over the two-week period from December 15th to 28th, an increase from last week when it had a rate of 659.7.
Armagh has the next highest rate, with the BT61 and BT60 postcodes reporting 954.1 and 937.9 cases per 100,000 in the fortnight to December 27th.
Postcode areas covering Newry (BT35), Enniskillen (BT74) and Ballymena (BT32) are all reporting 14-day incidence rates over 800 cases per 100,000.
Ballybay-Clones in Co Monaghan and Buncrana in Co Donegal have the next highest rates in the Republic, at 707 and 679.6 respectively.
Kenmare in Co Kerry has seen its incidence rate jump to 670, up from 438.9 last week.
Lismore in Co Waterford and Cahir in Co Tipperary were the only local electoral areas to record fewer than five confirmed Covid-19 cases in the 14-day period.
In Northern Ireland, the postcodes with the lowest rates are BT1 in Belfast, which recorded three cases over the two-week period, and Ballycastle (BT54) in Co Antrim, which recorded a rate of 149 cases per 100,000.
Testing delays
It comes as people who are close contacts of Covid-19 positive cases in the Republic will no longer be advised to get tested themselves, in a bid to take pressure off the system.
The State's chief medical officer Tony Holohan said symptomatic people are now regarded as a higher priority than those who are close contacts, with demand for testing rocketing.
People who are close contacts of positive cases are still asked to restrict their movements for 14 days.
A senior health official also confirmed the number of confirmed cases of Covid-19 in recent days is under-reported by an estimated 4,000, due to delays in recording positive test results on the system over the Christmas period.
Prof Philip Nolan said the reproductive number in the Republic is at least 1.6 to 1.8, and the daily growth rate is estimated at 7 to 10 per cent, giving a doubling time of seven to 10 days or less.
