IT'S hard to really conceive what a pandemic is until you've been through one.
There is undoubtedly still much we are experiencing now which we do not yet understand. But we know more than we did.
When the cases were low in Northern Ireland there was a slightly obsessive hunt for asymptomatic sufferers - Patient Zero and their contacts.
Returnees from Italian ski resorts (where a western European outbreak was believed to have originated) were looked at askance and there was some frankly racist hysteria around anything (or anyone) of Chinese origin.
Then came the day all coronavirus watchers had been dreading – when Northern Ireland began to see `community transmission', meaning it was no longer possible to trace the origin case.
The Rubicon had been crossed and the deadly virus was no longer `containable'.
This week there was a hark back to those days when mathematical modelling by a group of experts at Queen's University Belfast suggested seven people, who had been exposed to the disease but had no symptoms and weren't yet infectious on March 1, 2020 "imported Covid-19 to Northern Ireland".
Knowing, as we do now, that the region would go on to see almost a quarter of a million infections and thousands of deaths – with no real end in sight - it is a sobering moment.
Their work, using computer simulations and Department of Health data, is designed to help preparations for future variants and diseases and suggests "the outbreak could have entered the country undetected as it took some time for people to become infectious and develop symptoms".
Looking back now those early days of hoping to shut down the spread seem like Canute trying to hold back the tide.
New Zealand is grappling with its own feelings of futility after prime minister Jacinda Ardern has announced the end of the country’s elimination strategy.
It is switching to a `suppression approach', now aiming "to contain and control the virus" having stuck resolutely to a Covid-zero strategy for the past 18 months.
During that time New Zealanders have been living as if there was no pandemic in an idyll much envied around the world. "Well, New Zealand managed it," was a bitter refrain in countries where cases spiralled horrifyingly.
It felt like a cruel reminder of what could have been - perhaps if Northern Ireland had got a grip on those seven original `cases'.
Extremely low hospitalisations and deaths, few restrictions, low unemployment and a flourishing economy - it was like a different world.
Until Monday when the country finally had to admit defeat in the face of a two-month long battle with the Delta variant.
However, with just 40 per cent of the population fully vaccinated and low acquired immunity, inhabitants fear they may be on the precipice of the scenes that have dismayed the rest of the world.
Vaccination rates are particularly low among Maori, who are around two-thirds behind the wider population.
Elimination protected almost all New Zealanders, but community spread is likely to see higher rates among the poor, those with disabilities and ethnicities suffering other forms of disadvantage.
Its Green Party has warned the new policy will have too high a cost for the vulnerable.
Ms Ardern’s plan is for strict lockdowns to end once 90 per cent of the eligible population is vaccinated - making it one of the most vaccinated in the world.
Covid modellers warn if the policy fails a community outbreak could result in 7,000 deaths, and 60,000 hospitalisations.
To date it has recorded just 27 deaths.
Of course if the pandemic has taught us anything it is that we don’t know how any of it will end.
New Zealand has been forced to change course because of a variant which smashed through defences robust enough to withstand the original strain.
Dangerous mutations will continue until the whole world is vaccinated.
In a pandemic, as in life, none of us are safe until all of us are safe.
