Health Service Executive chief Paul Reid has warned of this "difficult phase" where he said people want to get "out and about" more and he highlighted the risks of social interactions.
Speaking on RTÉ's Morning Ireland, he said with the weather picking up, there are more people moving between homes, resulting in the virus spreading from one home to another.
"My main call is we don't lose everything we have done," he said.
He added that if people continue with the public health guidelines "we can be in good shape" to get out of this wave as soon as possible.
Mr Reid said while the indicators, including hospital admissions and intensive care unit cases, are going in the right direction, he expressed concern that the coronavirus is still at a high base.
He said that the is an overall positivity level of 5% and the positivity rate of close contacts is at 25%.
In a more upbeat note, he said the reopening of schools is giving people great hope and outlined how the HSE will be working to ensure the situation is monitored, working through a number of processes and with the Department of Education.
"Fifty inspectors are working with public health teams and plans are in place wherever cases emerge to do mass testing," he said.
The real risks are at the school gate, particularly with this variant, he said, and he has called on people to be conscious not to mix with people when transporting children to and from school.
Mixing at the school gate "the real risk" [for Covid-19 transmission] rather than children being in school, advises HSE chief Paul Reid pic.twitter.com/6mH4Vgxx8Z
— RTÉ News (@rtenews) February 26, 2021
Mr Reid moved to reassure people that everything will be in place for the ramping up of vaccines in April, with plans for one million doses to be administered every month.
He said vaccination centres will be ready to inoculate people, with 6,500 trained in the vaccination programme and a national recruitment campaign under way.
B1525 case in east of country
Dr Cillian De Gascun, Director of the UCD National Virus Reference Laboratory and a member of NPHET, has said the B1525 variant is a "variant of interest" because it has changes in the spike protein that may impact vaccine effectiveness.
The variant was first identified in Nigeria.
Speaking on RTÉ's News At One, Dr De Gascun said this new lineage accounts for just over 20% of cases in Nigeria.
He said that in contrast to other variants, such as the ones first identified in the UK and South Africa, this one has not become dominant in Nigeria, which suggests it does not seem to be more transmissible.
However, he said it is important that we continue to monitor it.
New variant B1525 has not yet become dominant in Nigeria and, while it has mutations of concern, it "doesn't appear to be more transmissible," says Dr Cillian De Gascun pic.twitter.com/Z7YJEhVQo5
— RTÉ News (@rtenews) February 26, 2021
One case of the B1525 variant has been identified in Ireland, which Dr De Gascun said is in the east of the country.
It is travel related, he said, and was flagged through a contact tracing centre.
He said there is a risk of onward spread with all variants, but the "good news" is that public health measures are effective in controlling these lineages.
In relation to 'sequencing', Dr De Gascun said that over the course of the pandemic "in or around 1%" of cases have been sequenced.
He said recent guidance from the ECDC and WHO shows that in order to have sufficient power within your sample to identify variants of concern at a low level, you would need to be sequencing between 5% and 10%.
He said we are now up to between 13% and 15%, and are doing in the region of 800 to 900 sequences per week.
"What we also need to do now in the longer term is put that on sustainable footing", Dr De Gascun said. "And I think the key thing to highlight here is that it's not just about the data, sequence numbers and laboratory capacity - we'll be working with the Health Protection Surveillance Centre and colleagues in public health to put in place an end-to-end surveillance programme, because there's no point in having data if you can't link it back to the individual and the public health investigation."
He said that ultimately, by the time you are sequencing, the cases have arrived.
It is an important component of the overall strategy, he said, but it is "not a silver bullet".
"Ultimately by the time you're sequencing, the [Covid-19] cases have arrived. It’s an important component of your overall strategy but it’s not a silver bullet," says Dr Cillian De Gascun pic.twitter.com/iHX6J3OsS3
— RTÉ News (@rtenews) February 26, 2021
"If you want to try and reduce the number of cases coming into the country, you really have to try and have measures around travel, which is obviously what the Government has been doing with pre-travel PCR and mandatory hotel quarantine that they're discussing at the moment."
Dr De Gascun said it is a "good starting point" but the question is whether it will be sufficient.
He said that from a public health perspective, they want to avoid non-essential travel, but there is a "suite of measures" including pre travel testing, quarantine on arrival and follow up testing, and "all of those components are important".
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Reid: We must reflect on what we could've done better
"I would like to see us reducing the restrictions in nursing homes," says HSE chief Paul Reid pic.twitter.com/XxAb9CBdNh
— RTÉ News (@rtenews) February 26, 2021
Meanwhile, the head of the HSE's testing and tracing system has said there will be more "investigative" reverse contact tracing, which will allow local notifications for anyone who has been in a particular place and time in the previous seven days, to present for a test.
Speaking on RTÉ's Today with Claire Byrne, Niamh O'Beirne said this is "extensive work" that will be carried out by public health doctors who are specialised in this field.
Ms O'Beirne said this work is already being carried out by public health doctors on "complex cases". but, she said, as case numbers fall this type of source investigation can be carried out on routine cases of Covid-19.
"At the moment, most of our focus is what's called 'forward tracing', which is stopping the transmission and finding close contacts.
"So this would be looking backwards and seeing if there's anything that could have been missed and any clusters that we can identify," she said.
Ms O'Beirne said this type of investigative work can begin when the number of Covid-19 cases drop in Ireland, "to less that 100 cases", and will use Eircodes to try to identify other people that should be tested.
"If you look at the countries that have very low levels of cases, that's what they do.
"Because it is an activity that you would do at a very detailed level, for example from an Ireland perspective you have less than 100 cases.
"We'll go back seven days for the individual and talk to places that they were. We will to take the Eircode of where they were.
"This will allow the Health Protection Surveillance Centre (HPSC) to do some pattern analysis, to see if they can look at other people in the same location and then they will contact that setting and see if there are other people that we can test and find other cases."
📻 HSE National Lead for Testing & Tracing, Niamh O'Beirne, tells #TodayCB investigative 'reverse contact tracing' can begin when the number of Covid-19 cases in the country drops "to less than 100 cases", & will use Eircodes to try and identify other people to be tested
— Today with Claire Byrne (@TodaywithClaire) February 26, 2021
On testing, Ms O'Beirne said antigen testing is approximately 50% accurate, and is best used in hospital or outbreak settings, "so a PCR test is a much better test".
"It [antigen testing] should be used in a symptomatic setting so like a hospital setting or in an outbreak setting, because you get better sensitivity when you use it in that setting."
She explained that antigen testing provides speedy responses and "early warning" to those settings, which allow the HSE or the National Ambulance Service to inform someone that they should leave a particular setting immediately.
Ms O'Beirne said that there could be an adverse effect in human behaviour by believing that antigen testing provides a high degree of accuracy.
"They are not the panacea. We have to think of human behaviour on seeing a not detected result.
"They might do things they may otherwise not have done and that's really important because the accuracy is only 50%, roughly, if you don't have any symptoms. So a PCR test is a much better test."
WHO expresses support for vaccine certification
The World Health Organization's Special Envoy on Covid-19 has said he is is hopeful there will be more opportunities for travel between EU countries in the summer.
Speaking on the same preogramme, Dr David Nabarro said he hopes it will go beyond travel agreed between two countries and believes in a few weeks there will be more clarity on such arrangements.
However, he said it will all depend on what is going on with the virus and how countries are able to coordinate protocols for travel.
"So just wait a little bit before making all your holiday plans. I think in a few weeks there will be much more clarity on what the arrangements for travel during the summer months are going to be," he said.
Dr Nabarro said travel bans cannot go on forever and success depends on being able to have people travel in and out of the country too.
He said there has to be a capacity in every country to pick up on the emergence of variants and when cases build up to be able to suppress it fast.
He agreed with having vaccine certification with all the relevant information as an extra assurance to know what people have been given, but expressed concerns about such documentation being used as a so-called passport in the immediate future.
"I am not quite personally ready to say that we are at that point. Simply because there is just not enough vaccine around and not enough people to be vaccinated really to be planning travel in the coming months on the basis on what some might call a vaccine passport," he added.
