On the point on which the Tánaiste has concluded, I raised with the Minister, Deputy Stephen Donnelly, yesterday the specific vulnerability of people who are in receipt of home care. They need to be specifically prioritised because they may have two to three different carers coming in every day and those carers are going into several houses every day, of necessity.

As someone who has repeatedly called for testing at airports, which I first raised with the Tánaiste and the then Minister for Health, Deputy Harris, last April, I welcome the introduction of an airport testing regime. I worry, however, that this particular testing regime may not achieve what it has set out to achieve and may in fact have some unintended consequences.

What is happening at our ports? Is there a similar testing regime at our ports and, in particular, in airports in Northern Ireland? I am aware that Belfast International Airport is offering testing for outgoing passengers but I am not aware of a similar requirement for incoming passengers. If there is not a similar regime for ports and airports in Northern Ireland, and indeed ports here, we are then effectively closing the windows to keep the cold out while leaving the front door open. We have an open border with Northern Ireland and there has to be a degree of co-ordination in that regard.

As the Tánaiste will be aware, it is generally accepted and was explained by Dr. Colm Henry to the Covid-19 committee that polymerase chain reaction, PCR, testing will identify as positive someone who has had Covid-19 recently but is no longer infectious. This specific query comes from a constituent but I am sure it is a common issue right across the country. One employee of my constituent went back to England for Christmas, developed Covid-19 and, like the majority albeit not everybody, recovered and is no longer infected by it. However, if this person does a PCR test now, it will be positive and will still detect Covid-19 for some time, even though the person is not infectious right now. Science would suggest that this person has the least chance of redeveloping it or becoming infectious, hence the suggestion that people not be vaccinated perhaps for six months because there is a period when the risk is relatively low. In those circumstances, are these people precluded from coming to Ireland even though they are essential workers and are needed for essential work? Can the test be modified in those specific circumstances for someone who has been positive and will therefore test positive, even though that person clearly is not infectious?

Under the new rules, any person entering the State through our ports or airports will have to have had a PCR test with a negative result within 72 hours of their arrival. The only exception that is being made is for people who are transport workers in that supply chain, such as hauliers, cabin crew and pilots, for obvious reasons. Some exceptions are made on compassionate grounds where someone needs to get back to the country very quickly because they may have a dying parent or child or something on those lines. Those are the only exceptions being considered at the moment.

PCR testing is not 100% and will miss some positives and there will be false negatives but it is the most accurate test that we have. Having had the PCR test does not mean that the person does not have to quarantine. The green, amber and red rules still apply as to restrictive movements and so on, once one arrives in the country. The objective in doing this is, first of all, to reduce the amount of international travel in order that only those who genuinely need to travel are doing so for essential reasons. The second objective is that by requiring the test one is reducing the risk. We have seen 97% to 98% compliance now with people flying in from Great Britain and it considerably reduces the risk.

People often ask why this was not done before. There are many reasons, not least of which was the availability of PCR testing months ago. The biggest problem with it is Northern Ireland and the fact that one can fly into Belfast, for example, from Britain, and perhaps even other parts of the world through Britain, without having a negative PCR test. This is something that we are engaging with the Northern Ireland Executive on but it is an area in which Sinn Féin, in particular, can be helpful. I often hear Deputy Doherty or Deputy McDonald on the TV and radio speaking as though Sinn Féin is not in government anywhere on this island. It is in Northern Ireland, it co-chairs the Executive there and has a responsibility to do the one useful thing it could do to help us battle the pandemic, which is to convince its coalition partners and the Northern Ireland Executive to bring in the same rules for people entering Northern Ireland from Britain and elsewhere. If we just do this here in the Republic, it will not be enough as it needs to be done in Northern Ireland as well. Constantly calling for an all-Ireland strategy is not good enough, as one has to do everything one can to achieve it. There is a particular responsibility now on the Sinn Féin Party, which co-chairs the Executive in Northern Ireland, to convince the other parties to do exactly that.

My specific question was whether the Government will look at exempting people who will test positive because they have had Covid-19, have gone through the symptoms and recovered, although they are not infectious and are essential workers.

The other thing that I have repeatedly called for is that NPHET and the Department of Health look at vitamin D supplements. We know that we cannot give the vaccine to everybody who requires it now but we can give vitamin D to everybody. I am not suggesting that it is as efficacious as a vaccine but the overwhelming evidence is that it is beneficial both in terms of preventing people getting Covid-19 and in reducing the impact of Covid-19 if they do get it. The risk of toxicity is very low so there is little to lose and much to gain. I asked the Department of Health this question and received a parliamentary reply saying that it would continue to look at the matter. There is more and more evidence being published in The Lancet and the British Medical Journal, that is, in reputable scientific journals, to suggest that benefits accrue from this while people are waiting for a vaccine.

For now, the only exceptions to having to have a negative PCR test result on coming into the country are if one is under six years of age, if one is part of the transport supply chain such as the pilot, cabin crew or haulier or for compassionate grounds where someone needs to race back to the country in an emergency. We can consider further exceptions into the future and I will take up what the Deputy has mentioned with our medical people and scientists. We want to see first how this works before we start adding new exceptions, which I believe the Deputy will understand. Thus far, at least with people coming from Britain, it is working very well. More than 97% of people arriving in Ireland from Britain through our airports have had the negative test. As to the other 3%, that is a matter for the Garda and the Director of Public Prosecutions, DPP.

The jury is still out on vitamin D supplementation. There is some evidence suggesting that it could be beneficial. I am not going to do a Donald Trump here and recommend remdesivir, chloroquine or anything else until we are in a position that we have more conclusive evidence as to whether it is beneficial. Again that is something I will take up with our medical people.

I thank the Tánaiste.