The letter sent from the Chief Medical Officer to Health Minister Stephen Donnelly following a NPHET meeting on Monday has been published in full.
Dr Tony Holohan sent a 13-page document detailing the threats posed by the Delta variant of Covid-19, the projection for the situation with the virus in the coming weeks, and NPHET's advice on lockdown measures.
The recommendations were taken into account by Cabinet ahead of Micheal Martin's address to the nation this afternoon.
The Taoiseach confirmed the return to indoor activities, including hospitality, will be delayed until at least July 19.
Mr Martin did not give an exact date when eating and drinking indoors will be allowed to resume, stating that NPHET's advice is that the return to indoor hospitality should be limited to those who are fully vaccinated and those who have recovered from Covid.
This advice from public health experts formed the basis of the announcement from Government today on the revised roadmap for reopening in July.
"Last night NPHET advised in very stark terms that reopening on July 5 poses great risk, so we have agreed to delay some elements of reopening," Mr Martin said.
"If we were to proceed as we had planned, we would significantly increase the risk of the pessimistic scenarios they've outlined. That would affect our health service and our mortality rates," he added.
That "stark" advice has now been published in its entirety by the Department of Health, with grim projections laid bare by health officials on what would happen if restrictions were lifted on July 5 as planned.
Dr Holohan said the current epidemiological situation in Ireland is "broadly stable" in terms of the incidence rates, numbers of cases in hospital and ICU, along with "significantly lower" deaths associated with the virus compared to recent months.
"However, this is set against a background of rapidly increasing prevalence in Ireland of the Delta variant which is significantly more transmissible and less susceptible to vaccines than previous variants," he said.
"This poses a very substantial threat, particularly to those who are not yet fully protected through vaccination."
He added that the extent to which people will require hospitalisation as a result of contracting the virus in the coming weeks is uncertain.
"What is clear is that the Delta variant, with it is clear transmission advantage over the Alpha variant, is rapidly becoming the dominant strain, and in our partially-vaccinated population, the increased risk of onward transmission associated with this variant makes a significant fourth wave of infection likely," Dr Holohan warned.
"What is uncertain is the magnitude of this fourth wave, and its severity in terms of hospitalisation, mortality, and long-term sequelae."
The uncertainty largely related to how much more transmissible the Delta variant is compared to previous strains, as well as the protection offered to people depending on their vaccination status.
"The difference in vaccine effectiveness in preventing infection means that as Delta comes to dominate there is a fraction of the population with only one dose of vaccine who are at increased risk of becoming infected, of transmitting that infection to others, leading to a surge of disease in an incompletely protected cohort," he said.
Given this ambiguity, NPHET modelled five scenarios based on the return of indoor social mixing and the increased transmissibility of the Delta variant compared to previous strains.
All scenarios anticipate that case counts "rise very slowly" throughout July 2021, Dr Holohan acknowledged.
However, he stated: "The seeds of future growth are sown at this time, and case counts increase exponentially through August 2021 until a combination of vaccine-induced and infection-induced immunity slows growth through September and October 2021.
"The infections occur largely in the young, unvaccinated population, but as the force of infection grows, a significant number of infections also occur in older, vaccinated people."
NPHET's 'optimistic', or best-case scenario, projections predict that between July 1 and September 30, there would be 81,000 cases, 1,530 admissions to hospital, 195 admissions to ICU, and 250 deaths.
While 75% of the cases would be in people under 40, 99.9% of the deaths would be among those aged over 40 years of age.
However, the health emergency team also offered 'pessimistic projections showing a worst-case scenario if restrictions were lifted.
This would include 681,900 cases, 12,985 hospitalisations, 1,685 ICU admissions, and 2,170 deaths, also between July 1 and September 30.
Despite these bleak indicators, Dr Holohan wrote that "the epidemiological situation has been improving or stable over the last number of months, and the gradual relaxation of measures has not to date resulted in any noticeable increase in incidence of infection at a population level".
He continued: "There has also been considerable improvement in the level of hospitalisations and mortality. In addition, there continues to be very significant progress made by the Covid-19 Vaccination Programme, with high uptake across all cohorts to date.
"As referenced in previous letters, the protection provided by vaccination is already changing the relative risk profile at a population level and will continue to do so over the coming months. "
In light of modelling projections, ECDC advice and emerging evidence of the impact of the Delta variant in the UK and other countries, NPHET issued these recommendations to Government:
- "The increase in the numbers permitted at outdoor events can proceed as planned from the 5th July, increasing to a maximum of 200 attendees for the majority of stadia, and to 500 for stadia/venues with capacity greater than 5,000"
- "The other measures which were due to be eased on the 5th July which, by their nature are high risk activities which will involve significant levels of social mixing in indoor environments, should only be permitted for those who have been fully protected by vaccination or who have had Covid-19 infection in the previous nine months"
- "The planned easing of these measures should only proceed once a robust, non-reproducible and enforceable system of verification of vaccination or immunity status can be put in place to support this. If this is not deemed feasible, the Government should consider pausing further easing of these measures until such a system can be instituted"
- "The current vaccine bonus applicable to household visits should be revised as follows:
- - There should be no limit on the numbers of people that can visit together once they are all fully protected by vaccination or have had Covid-19 infection in the previous nine months i.e. the limit of three households can be removed. The advice for household visiting remains unchanged for those who are not fully protected by vaccination
- - Given emerging evidence in relation to the effectiveness of one dose of the AstraZeneca vaccine against the Delta variant, the vaccine bonus measure should only apply two weeks after the second dose of the Astra Zeneca vaccine i.e. it should no longer apply 28 days after the first dose"
- "Given the possible deterioration in the epidemiological situation through July and August 2021, and the potential impact that could have on educational settings in Autumn 2021, the NPHET further recommended that the HSE complete its review of the epidemiological profile and public health response to Covid-19 in educational settings to date, and put measures in place so as to ensure that the public health response to Covid-19 in these settings remains robust and responsive to emerging trends in those settings"
- "There should be ongoing work to strengthen communications, with targeted messaging for vaccinated and unvaccinated people, ensuring that both groups have clear information and advice on safe activities."
Dr Tony Holohan concluded that the public health advice remains that higher risk activities, including international travel for those who are not fully vaccinated or immune, are recommended against.
