Last week, a report by the Central Statistics Office (CSO) concluded that there have been between 900 and 1,200 extra deaths this year compared with other years. This is called the number of 'excess deaths'.
From year to year, the overall mortality rate in Ireland, and indeed most countries, is remarkably stable. We can therefore spot if more people are dying. It is perhaps the most important number to examine when it comes to Covid-19.
People who criticise governments' approach to Covid-19 look at this number closely and say: 'What's all the fuss about when excess death numbers are relatively low?'
Debate then ensues, with defenders of lockdowns and restrictions saying that the number is being kept low because of all the things we're doing. Critics will say if there are excess deaths, these could be due to the policies being followed.
Maybe the Government's response to Covid-19 is harming people, by, for example, somehow causing more deaths because people are not being diagnosed and treated for other diseases. It is therefore a fraught business and we need accurate data to get the true picture.
The data from the CSO in Ireland certainly points to excess deaths. It's difficult to get an accurate number overall, however, as if total deaths are examined, there may well be decreases in deaths from other causes - for example fewer accidents at work because fewer people are going to work. Fewer traffic accidents because of fewer cars on the road.
There may, however, be increased deaths because of people not getting treated for other diseases, or for example because of increased drug abuse or domestic violence. This makes the interpretation of excess deaths difficult.
Other studies are also reporting excess deaths. A new report from the US Centres for Disease Control and Prevention (CDC) has concluded that nearly 300,000 more deaths than expected have occurred in the US so far in 2020.
Donald Trump's critics blame him for these deaths. Two-thirds of these have been caused directly by Covid-19.
This means that one-third of the excess deaths are not associated with Covid-19. But again, there are difficulties.
The CDC have said it's possible that deaths on both sides - Covid-19 and non-Covid-19 - might have been misclassified. Strange as it may seem, there are inaccuracies in the reporting of what someone actually dies from.
Even though a person may have tested positive for Covid-19 before they died, it doesn't mean Covid-19 is responsible for their death.
Equally, if someone died of a heart attack, this could well have been provoked by Covid-19, which is known to damage the heart.
Some even say that if an older person's death is attributed to Covid-19, they may well have died of old age anyway, and all that has happened is this has been hastened. Remember though, in both cases the person would not have died were it not for Covid-19.
The CDC report also concludes that deaths from heart disease, stroke, Alzheimer's disease and lung diseases have all increased in 2020.
But it's unclear to what extent these represent deaths provoked by Covid-19, or deaths indirectly related to the pandemic, for example because of disruptions to health care access or utilisation.
There are real concerns in the US and also in Ireland that people are putting general healthcare treatments on hold, either because of reduced access to treatments or people being scared to go to hospital for fear of infection.
There have been reports in several countries of a drop in cancer diagnosis compared with other years. In the US, there are also reports of an increased number of drug overdoses, with some indications that these might reach record levels for 2020.
Is the stress of Covid-19, both economic and psychological, giving rise to increased drug use to provide relief?
It also turns out that in the US certain sections of society are faring worse. The excess death rate is higher in Hispanic, black and Asian communities compared with white people.
When the age of people who are dying is examined, excess deaths are mostly happening in older people.
No surprise there. But the CDC also reports a spike in excess deaths in people aged between 25 and 44.
This is important, as it indicates that Covid-19 is not only a disease of older people.
And worse, the modellers have examined the trajectory of excess deaths, and they are predicting that by the end of 2020, there will be more than 400,000 excess deaths in the US.
What about other countries? A recent study examined 21 industrialised countries over a period from mid-February to May 2020.
It concluded that 206,000 more people died in these countries than would have, had Covid-19 not occurred.
The number of excess deaths was similar between men and women in most countries. England, Wales and Spain had the greatest number of excess deaths.
The excess death rate in most countries began to climb in March, correlating with the spread of Covid-19. This gives confidence that the deaths are being caused, directly or indirectly, by Covid-19, given what we know about the effect the virus has on our bodies.
The number of deaths in this three-month period is the same as the number of deaths from lung cancer for a whole year, and twice the number of deaths from diabetes or breast cancer for an entire year.
Overall, 18pc more people died in this period than normal, with 28pc more people dying in England and Wales.
The study also lists the indirect effects of Covid-19 and responses to it.
These include denied or delayed medical procedures; loss of jobs and income; a growth in self-harm and crime, especially domestic abuse; changes in quantity and quality of food; the use of tobacco, alcohol and other drugs.
Can we determine whether government policy in the countries examined was causing deaths to happen?
Sweden gives us the best evidence that this is not a major factor. In the time examined, it was the only country that did not put in place a mandatory lockdown.
It had one of the longest durations of excess mortality, suggesting that if the government had introduced restrictions, there would have been fewer deaths.
However, the study also concluded that lockdowns have adverse short- and long-term health, psychosocial and economic effects which will increase the excess death number, although this may take time to reveal itself.
Might lockdown mean short-term gain but long-term pain? We have to hope not, but must prepare for this possibility, and be especially conscious of the long-term effects of damage to mental health. The analysis of excess deaths will therefore continue. It is highly likely the measures our Government has taken will continue to bring the death rate down.
Improved survival rates in hospital as doctors learn more about how to treat patients, and the arrival of newer treatments, will also be evident.
We can therefore look forward to the excess death rate continuing to decrease. We will then be able to conclude that what we've been doing will have worked.
Unlike in the US, where effectively people were allowed to die of Covid-19, we will have protected our people.
We will hopefully be able to look back on this annus horribilis in the knowledge that we did the right thing.
We protected the vulnerable as best we could and learnt a huge amount to take us into the future with confidence, when Covid-19 becomes endemic in our population, but is not something to be as frightened of. Here's hoping.
Luke O'Neill is professor of biochemistry in the School of Biochemistry and Immunology at Trinity College Dublin