Almost one in every 50 people in Carndonagh, Co Donegal had coronavirus over the last two weeks, according to the latest official figures.
The most northerly electoral area in Ireland has the highest rate of Covid-19 on the island with an incidence rate of 1,975 infections per 100,000 people. The area reported 335 cases among its population of 16,964 people in the latest 14-day period.
Other areas in Co Donegal with high incidence include Buncrana (1,239 cases per 100,000) and Donegal town (608).
The next worst affected region is Belfast, with several postcode areas in the city reporting infection rates of more than 1,000 cases per 100,000.
The BT13 and BT12 postcodes, which cover much of west Belfast, have the highest incidence rates (1,950 and 1,450 respectively), while infections are also climbing in nearby Whiteabbey, Co Antrim (1,359), and the Ardoyne area of north Belfast (936).
The total number of hospital admissions in the Belfast Health Trust have doubled over the last week, from 27 to 60.
Chris Hagan, the medical director of the Belfast Trust, told the BBC there was “significant pressure on services” and said the highest number of infections were in the 20-39 age group.
Other areas where coronavirus is spreading more widely include Strabane, Co Tyrone (1,075), Derry City (1,034), Newry, Co Down (1,008), Castlewellan, Co Down (827), Ballycastle, Co Antrim (808) and Ardee, Co Louth (774).
The figures are based on the number of new cases in the Republic’s 166 local electoral areas and the North's 80 postcode areas over the most recent two-week period.
Ongar in west Dublin has the highest infection rate in the capital, with 578 cases per 100,000 people, up from 427 last week. Rush-Lusk has the lowest rate in Co Dublin at 182 per 100,000, up from 27 last week.
'Big hurdle'
According to the head of the HSE, the threat of the Delta variant is a “big hurdle” the country has to overcome in its battle against Covid-19.
In his weekly briefing, Paul Reid said the five-day and seven-day averages in the Republic have jumped by 160 per cent and 150 per cent respectively compared to two weeks ago.
Compared to last week, the overall 14-day incidence rate in the Republic is up more than 66 per cent.
Health officials say their concerns about the potential impact on hospital numbers over August remains high.
Meanwhile, a senior health official has suggested that nine out of 10 people will have to be vaccinated to reach herd immunity against Covid, raising the prospect of a mass vaccination programme for children.
Dr Colm Henry, the HSE's chief clinical officer, said the arrival of the “more transmissible” Delta variant meant “to reach that concept of herd immunity, which every country is far away from yet, the estimate has gone up to 85-90 per cent”.
In the North there is growing concern over vaccination rates stalling among younger age groups.
Within the 18-29 age group, just 56 per cent have come forward for the vaccine.
Northern Ireland Executive ministers were told at a meeting on Thursday that a 5 per cent increase in uptake of the first dose from 85 per cent to 90 per cent would result in a 50 per cent decrease in cases and hospital admissions at the peak of the current wave of infections.
