Ireland is facing a prolonged period of very strong social distancing measures if coronavirus is to be suppressed, a Government adviser has warned.
Professor Philip Nolan, who heads the National Public Health Emergency Team’s statistical modelling group, said the restrictions were designed to ensure Ireland would not experience any “surge” in cases but rather a long period with a large number of cases spread equally across that time frame.
He said the strategy was about suppressing the disease, not eliminating it.
The leading academic said if mitigations had not been taken to prevent the spread of the disease, Ireland would be seeing a peak in 20 days’ time of 100,000 cases per day.
He said limited steps, such as the closure of schools, would have seen a peak in 40 days’ time of 60,000 cases per day.
Prof Nolan expressed confidence that the current lockdown on movement across the state would mean there would “barely be a peak detectable at all”.
“We will be requiring very strong social distancing measures for some prolonged period of time in order to keep the disease suppressed for the length of time that we need to,” he said.
The professor said Ireland would only be in a position to assess how restrictions may be changed or relaxed when it gathers enough evidence from other countries that have taken similar steps.
The coronavirus death toll in Ireland rose to 263 on Thursday, with 28 further deaths reported since Wednesday.
There were 500 new confirmed cases of the virus in Ireland, taking the total in the country since the outbreak began to 6,574.
Prof Nolan said social distancing was having a “profound effect”.
He said the day-on-day growth rate of the virus had dropped from more than 30% to 9%.
“We’ve been monitoring the epidemic very closely,” he said.
“And, as I would have said last week, there’s clear evidence that the social distancing measures that are designed to reduce the transmission of the virus are having a very profound effect on the transmission of the virus.”
On the slowing growth rate, he said more progress was needed.
“Frankly, that number needs to be zero in order to have control or suppress this epidemic,” he said.
Prof Nolan said the reproductive rate – the number of people infected by each infected person – had also fallen significantly.
He said it had decreased from around four at the beginning of the outbreak to “very close to one”.
The professor said one was the pivotal number as a reproductive rate only slightly above one would mean the virus would continue to grow.
He said if the rate fell below one then cases would start to decline.
We should flatten this curve so much that we're distributing over a long period of time and there isn't an identifiable surge or peak within thatProfessor Philip Nolan
The academic said the social distancing measures were designed to ensure Ireland would not experience a so-called “surge” in cases.
“We shouldn’t be expecting a surge, we shouldn’t be expecting a peak,” he said.
“We should flatten this curve so much that we’re distributing over a long period of time and there isn’t an identifiable surge or peak within that.”
Ireland’s chief medical officer Dr Tony Holohan said that, as of Tuesday, there were 317 separate clusters of cases in Ireland.
He said of the confirmed cases at that point, around 24% resulted in a hospital admission and 3.6% in ICU admission.
Dr Holohan said 27% of the confirmed cases were healthcare workers.
He expressed concern that people with other health problems were showing reluctance to seek medical help during the epidemic.
Dr Holohan also said there was no evidence that people returning to Ireland from the Cheltenham racing festival in March had a significant impact on the transmission of the virus in the country.
On the data presented by Prof Nolan, Dr Holohan said: “The goal of our management is about the prevention of the transmission of this virus.
“The information that Professor Nolan has shared with you this evening is that we have very substantially impacted that and these curves are telling you that we have, as a country, saved many people’s lives, saved hospitalisation, saved admissions to intensive care units in very large numbers as a consequence of this.
“But it’s come at a significant cost in terms of the impact we have had to endure as a society.”