Archive for pandemic

Pandemic Memories, Five Years On

Posted in Biographical, Covid-19, Education, Maynooth with tags , , , on March 13, 2025 by telescoper

At the start of my Computational Physics lecture at 9am this morning I suddenly remembered that it was the corresponding day five years ago that Covid-19 pandemic restrictions were introduced in Ireland. The date for that was Thursday March 12th 2020, while today is Thursday March 13th 2025, but it was the same stage of of the semester, the Thursday before St Patrick’s Day and the mid-term Study Break.

One thing I remember quite well from that day five years ago was that I told my Computational Physics class to keep an eye on their email during the day as I thought an announcement would be made. When it came – around lunchtime, if memory serves – it was much stricter than I had anticipated: from 6pm that day, all schools, colleges and cultural institutions were to close until 29th March. Few people believed that would be the end of it, and we were right!

I had a computing laboratory session that afternoon, which went ahead, but some students understandably left early as they had to find their way home. The next time I interacted with any students it was online, and remote working carried on for many months, not just the two weeks originally planned. I did not envisage it would last so long. Nor did I imagine how little support teaching staff would receive from management. Indeed, the University saw the opportunity to build up large surpluses during the lockdown, all generated by the huge amount of extra, unacknowledged and unrenumerated, work put in by academics and support staff. That’s all money that should have been spent on the education of students. It was never going to be easy to teach during lockdown, but deliberately withholding resources made it far harder than it had to be.

Among other things, the Covid-19 pandemic restrictions played havoc with my perception of the passage of time and messed with my memory. I remember some things very clearly, such the lecture and lab on the day the restrictions were announced, which seem like they happened a few weeks ago never mind five years. Other things are like ancient history. Several major life events took place during the Covid-19 period period that I find it hard place in chronological order without looking at written records (including this blog).

I am not an expert on such matters but it seems to me that the isolation, disruption of social interaction, and the loss of familiar routines imposed by work are among the things responsible for distorting one’s perception of the passage of time and powers of recall.

It was not just the disruption to routine of course. There was also a genuine fear of becoming infected. From time to time after my last in-person class on March 12th 2020, I wondered if I would ever see those students again. I also made arrangements to write a will. For a time it looked likely that intensive care facilities in Ireland might be overwhelmed so I felt it important to make contingencies of that sort. Fortunately they weren’t needed. As far as I know the Coronavirus never reached me, though I think even those of us who were never infected by Covid-19 were definitely affected by it.

The Coronavirus Vaccine Effect

Posted in Covid-19, mathematics with tags , , , , , , on December 12, 2021 by telescoper

When I was updating my Covid-19 page today I thought I would try something a bit different. Here are the cases and deaths (in the form of 7-day rolling averages) as I usually plot them:

You can see a slight recent downturn – the latest 7-day average of new cases is 4214.3; it has been falling for a few days. A log plot like this shows up the changing ratio between deaths and cases quite well, as in l if you multiply a quantity by a factor that manifests itself as a constant shift upwards or downwards. There is clearly a bigger shift between the orange and blue curves after 500 days than there is, say, between, 300 and 400.

(I don’t think you can read much into the gap between the curves at the beginning (up to around 100 days in) as testing coverage was very poor then so cases were significantly underestimated.

Anyway, to look at this a bit more clearly I plotted the ratio of daily reported deaths to daily confirmed cases over the course of the pandemic. This is the result:

The sharp downward glitches occur whenever the number of reported deaths is zero, as log of zero is minus infinity. The broader downward feature after about 300 days represents the period in January 2021 when cases were climbing but deaths had not caught up. To deal with that I tried plotting the deaths recorded at a particular time divided by the cases two weeks earlier. This is that result:

The spike is still there, but is much decreased in size, suggesting that a two week lag between cases and deaths is a more useful ratio to look at. Note the ratio of deaths to cases is significantly lower from 500 days onwards than it was between 200 and 400 (say), by a factor a bit less than ten.

This obviously doesn’t translate into a direct measure of the efficacy of vaccines (not least because many of the recent cases and deaths are among the minority of unvaccinated people in Ireland) but it does demonstrate that there is a vaccine effect. Without them we would be having death rates up to ten times the current level for the same number of daily cases or, more likely, we would be in a strict lockdown.

On the other hand if cases do surge over the Christmas period there will still be a huge problem – 10 % of a large number is not zero.