One in every 50 people in parts of Armagh, Mayo and Limerick had coronavirus over the past fortnight, new figures show.
The latest Covid-19 data from electoral areas in the South and postcode areas in the North show how the disease is spreading in different communities.
Both sets of statistics use the incidence rate of infection per 100,000 population, giving a better understanding of an outbreak than straight case numbers.
The BT60 postcode in Co Armagh had the highest infection rate on the island of Ireland during the latest two-week period. The area, which includes part of Armagh city and borders Co Monaghan, saw 2,284.7 cases per 100,000 recorded from December 21st to January 3rd. This has more than doubled from last week when the area saw a rate of 937.9.
The worst-affected area in the Republic was Belmullet, Co Mayo, where 266 people had the disease over the two-week period from December 22nd to January 4th. That amounted to an incidence rate of 2,111.1 per 100,000 people, more than three times the national rate.
The next worst-affected area was Adare-Rathkeale, Co Limerick, with an infection rate of 2,010.1.
Tramore-Waterford City West saw its incidence rate jump to 1,010.2, up from 152 last week. Tramore GP Dr Austin Byrne said he has traced the spike in cases in the area back to “several events” that occurred indoors in the town over Christmas week.
Lismore in Co Waterford was the area with the lowest rate of infection in the South, reporting 103 cases per 100,000.
In Northern Ireland it was the BT77 postcode in Co Tyrone, which recorded no cases during the 14-day period.
Hospital pressure
The mounting caseload is putting pressure on health services across the island.
More than 1,000 patients are now in hospital with Covid-19 in the Republic.
Paul Reid, chief executive of the HSE, said the country faced an “extraordinary national crisis”.
Meanwhile, hospitals in Northern Ireland have cancelled some operations due to a surge of patients with coronavirus.
All of the health trusts in the North have reduced the number of planned operations. The Belfast trust said it had made the decision to cancel all planned inpatient surgery this week due to rising numbers.
