Zero Covid Ireland and Trips Abroad

 It might not be possible to have zero covid Ireland because too many people have to come into and out of the country. How many trips into and out of the country are necessary? This is an attempt to get some figures together because I have found no figures being actually argued just people saying 'Ireland is not New Zealand'

Irish born people living abroad coming home for sick relatives, funerals etc. Close to a million people born here live abroad. Say 10% have to return in a year that would be 100K.

Foreign born people having to go home for sick relatives, funerals etc. CSO data on Foreign born people is at Total is 393,959 people. 400K say. How many would have to travel? Say 10% a year or 40K.

Lorry Drivers About 150K Lorry journeys take place into Ireland each year. How many individual drivers? Say 10k I'll ignore drivers for the moment but they are an issue.

Border travel. About 25K people cross the border to work. But I will assume an all island approach for the moment. I did some NI calculations in this post

No quarantine or vaccine is going to be 100% effective. But it does not have to be just the number of cases coming in has to be kept low. For argument's sake say 1 per day can come into the country (not just a hotel) and later develop symptoms.  150K people having to come into Ireland per year. Or about 400 a day. 10 day quarantine means you'd need 4000 hotel spaces. Even after 14 days in quarantine about 5% of those infected could still develop symptoms later. At 400 per day where 1% of people carried an infection would be 4 people. 5% of those would be one person every 5 days would do quarantine and still have an infection after it finished. Requiring those coming in to be vaccinated might change these odds significantly to the better but not in an easy to calculate way yet.

New Zealand has a high foreign born population. 1.27 million live there who were born outside NZ. They also have a lot of people born there abroad who might need to come home about 14% which is only slightly lower than Ireland.

Back of the envelope if 10% of people have to go home per year. And we have a long quarantine that is enforced. We could keep cases introduced to quite a low number.