A fresh spike in Covid-19 cases is being driven by a rise in infections among second-level schoolchildren as well as large workplace outbreaks.
The 617 new cases recorded on Thursday is the highest for three weeks, prompting fears of a resurgence of the disease after weeks of improving figures.
However, National Public Health Emergency Team officials said they believed the increase in school cases would be transient and that the situation was still improving.
The number of school outbreaks rose from five last week to 26 week, while childcare outbreaks increased from 11 to 17, the Nphet briefing heard.
Deputy chief medical officer Dr Ronan Glynn said all but two of the school outbreaks involved fewer than 10 cases.
Dr Glynn singled out Donegal, Offaly, Kildare, Longford and Dublin as counties with rising transmission.
Workplace outbreaks, some with up to 70 cases, were a feature in these counties, he said. In Donegal, there have also been outbreaks linked to household mixing and birthday parties, while funerals and wakes around the country have also given rise to clusters.
Cases also rose in the 19-24, 40-64 and 65-74 year-old age groups.
A further 10 deaths of Covid-19 patients were reported by Nphet.
Seven of the deaths occurred in April, and one apiece in March, February and January.
This brings to 4,866 the total number of deaths in the pandemic.
Those who died ranged in age from 62 to 104 years and the median age was 82.
The reporting of 617 new cases brings to 245,310 the total number of cases in the Republic.
Of the new cases, 236 were in Dublin, 84 in Donegal, 37 in Kildare, 34 in Tipperary and 30 in Offaly, with the remaining 196 cases spread across 20 other counties.
The reproduction number, a measure of how many other people a case infects, now stands at “very close to 1,” according to Prof Philip Nolan, chair of the Nphet epidemiological modelling advisory group.
The number of close contacts remains at 2.6, which Prof Nolan described as
“a phenomenal testament to the public” in keeping social transmission low.
“All indicators of the disease are stable or declining slowly, though we may see an increase in cases over the coming days,” he warned.
Prof Nolan said the situation was broadly positive but there has been “a small spike in cases” in recent days. Hospital admissions have also increased in recent days and this will have to be “watched”.
The increase among 13-18 year-olds is likely to be transient, based on what happened when primary schools re-opened earlier in the spring and a similar rise occurred, he said.
Vaccination of the most vulnerable “changes the risk attached to the whole population,” according to chief medical officer Dr Tony Holohan.
Making his first remarks upon returning to work following the death of his wife in February, Dr Holohan said the situation had changed substantially in the time he was away, due to changes in the transmission patterns of the virus and the wider vaccination of people.
As more of the population are vaccinated “it changes the calculus as we approach the estimates as to what’s appropriate from a public health point of view”.
The “wonderful addition” of vaccination has helped control the risk posed by the disease, he said. “It’s a hopeful situation but we’re not yet where we want to be. There’s more work to do.
“We are in a strong position in that transmission levels have reduced substantially and the roll-out of vaccination is protecting more and more of those at risk from the severe effects of Covid-19.
“If we can maintain our current position there is hope that we can look forward to a real easing of measures, but it is as important as ever that we don’t put that progress at risk by letting our collective guard down too much, or too early.”
While there is good reason for “hope and confidence”, the key thing is that “we don’t find ourselves in a situation where restrictions are eased, and the public gets ahead of us in terms of anticipatory behaviour.”
“This would put the progress we have made at risk.”
“Now is not the time for house-parties,” he said.
There “are “reasons for real hope” that Ireland “can confidently move to a point” where an easing of restrictions can be recommended to Government, he said.
He said he was “a little concerned” about the rise in case numbers in recent days and this will have to be examined before Nphet provides advice to Government on the further easing of restrictions.
Dr Holohan said Nphet expected to receive advice from the National Immunisation Advisory Committee on the use of the Johnson&Johnson vaccine on Monday.
The 14-day incidence of the disease now stands at 118 cases per 100,000 people nationally. Donegal and Offaly have the highest county incidence, followed by Sligo. Kilkenny has the lowest incidence.
The median age of cases is 33 years and 70 per cent are under 45.
From May 4th, the number of visits allowed for nursing home residents is being increased from two to four, the briefing heard.
Under new guidance agreed by Nphet, increased visits are being permitted in home where most residents and staff have been vaccinated.
On Thursday morning, 176 Covid-19 patients were hospitalised, of which 48 were in ICU. There were 19 additional hospitalisations in the previous 24 hours.
By Tuesday, 1,240,965 doses of vaccine had been administered, with
878,823 people receiving first doses and 362,142 people getting second doses.
Meanwhile, new data from the Health Service Executive shows there were 29 cases of coronavirus detected among people in hotel quarantine up until Monday, an increase of 11 on the figure the previous week.
So far 1,355 swabs have been used to test residents, while a further 338 swabs have been used for testing hotel staff.
Incoming travellers from designated states are required to pre-book accommodation in a designated quarantine facility. Passengers who have travelled from or through “red list” countries are tested within 36 hours of arrival into Ireland and on Day 10 of their mandatory hotel quarantine. Hotel staff are tested on a weekly basis.
The weekly HSE report detailing figures on testing and tracing also shows there was a positivity rate of 2.2 per cent across 31 primary schools tested last week. In 18 secondary schools the rate was 0.5 per cent. The rate in primary schools has hovered between 1.3 per cent and 2.2 per cent over the last four weeks, while it has been under 1 per cent in secondary schools for the last three weeks.
The data shows that the positivity in childcare facilities remained stable over a two-week period after dropping from 5.7 per cent during the week until March 27th to 4 per cent last week. One special school, where 127 individuals were tested, returned a positivity rate of 1.6 per cent last week.
Serial testing in nursing homes is showing a positivity rate that is continuing to decline as the vaccine effect kicks in. Almost 50,000 tests have been carried out in nursing homes since March 29th, with 52 cases of the virus detected, giving it a positivity rate of 0.11 per cent. A similar rate (0.12 per cent) has been found in mental health facilities, where two cases have been identified among 1,669 people tested since March 29th.
Food production facilities had marginally higher rates of detection (0.33 per cent), although this figure is also declining. Since April 6th, more than 12,500 tests have been completed and 42 cases of the virus identified.
The average person testing positive for the virus last week had 3.3 close contacts. Of close contacts referred for testing up in the week to April 11th, 87 per cent attended appointments. Twenty-two per cent of those contacts tested positive for the virus, while the rate for household close contacts was higher, at 32 per cent.
Up to Tuesday, April 20th, 1,124 cases have been detected at walk-in centres across the State. A further three walk-in test centres opened across Dublin last week, while another opened in Tipperary. Since Wednesday walk-ins have been accepted at the test centre in Tralee, Co Kerry.