The Covid-19 pandemic has, in just a few months, brought the global economy to a halt and changed society and our daily lives in ways that were previously unimaginable to many.

The virus has already killed more than one million people around the world with more than 38 million cases at the time of writing. Despite this tragic toll, the total mortality impacts of the pandemic are likely to be greater than this already.

The mortality impacts of Covid-19 can be broadly grouped into three:

• Direct effects - individuals contracting the virus and dying from the disease;
• Indirect effects - of both the health system pivoting to focus on Covid-19 and individual behaviour change whereby patients do not seek medical attention for symptoms such as chest pain as early as they might ordinarily do so will affect chronic disease mortality rates;
• Social and economic conditions - resulting from the pandemic are likely to have substantial impacts which will be felt unequally across communities and the nation – a similar rise in unemployment to that seen after the 2008 recession would be expected to lead to 900,000 more working age people with chronic medical conditions.

‘Excess deaths’ from all-causes (how many more deaths there have been in total compared to what we would expect normally) are therefore seen as the most comprehensive measure to assess the full extent of the pandemic and to inform ongoing strategy. The Office for National Statistics and the Financial Times reported excess deaths throughout the early stages of the pandemic. Outside of my role at LCP, I am part of a group at the School of Public Health, Imperial College London. This group used an ensemble of statistical models and historical mortality data by age group and sex from 21 industrialised countries to estimate the number of deaths that were likely to have occurred from mid-February until the end of May this year had the pandemic not happened. The study was published in Nature Medicine on 14 October. The models account for a number of important drivers of mortality trends including ambient temperature, seasonality, where bank holidays lie in a year as well as the short and longer term age, sex and country specific mortality trends. This enabled the observed levels of deaths to be compared to the forecasted levels to then calculate excess deaths for the first wave of the Covid-19 pandemic.

Across the 21 countries studied:

• Australia, Austria, Belgium, Bulgaria, Czechia, Denmark, England and Wales, Finland, France, Hungary, Italy, Netherlands, New Zealand, Norway, Poland, Portugal, Scotland, Slovakia, Spain, Sweden and Switzerland – there were 206,000 excess deaths over this period representing an 18% increase in deaths compared to what would have been expected.
• This total mortality impact, however, was not felt equally. One group of countries (Bulgaria, New Zealand, Slovakia, Australia, Czechia, Hungary, Poland, Norway, Denmark and Finland) had no detectable increase in all-cause mortality during this period.
• At the other extreme, England & Wales, Spain, Italy, Scotland and Belgium experienced the largest increases in excess deaths. England and Wales and Spain felt the largest impact with approximately 37% and 38% increases in deaths respectively during this period.

There were several other noteworthy findings. Firstly, excess deaths were 23% higher than deaths recorded as Covid-19 deaths. This ‘gap’ between all cause excess deaths and Covid-19 deaths was largest in Spain (69%) and Italy (46%) respectively which could be due to:

1. Undetected Covid-19;
2. Whether registering as a Covid-19 death required a Covid-19 test and;
3. Indirect deaths from other causes as a result of the pandemic as discussed earlier.

Secondly, the death toll was surprisingly even across sexes with around 100,000 deaths in women and 105,800 deaths in men and thirdly, as we would expect, the mortality impact was much greater in the older (above 65 years) adults. While excess deaths in the over 65s were highest in Spain, England and Wales experienced the largest increase in excess deaths in young and middle-aged adults.

There are several possible explanations as to why the total mortality impacts from wave 1 of the pandemic varied so much across countries. Some will only become clear with the fullness of time, however there are several important lessons to be learned as we enter the second wave. The contributors to excess deaths from the pandemic can be broadly grouped into:

1. The public’s health;
2. The resilience of health, care and public health systems when the pandemic hit and;
3. The policy response to Covid-19.

The first group includes obesity and diabetes prevalence – two conditions that increase the risk of poor outcomes form Covid-19 infection substantially – as well as relative inequalities, population density and the portion of population above 65 years. The second group includes intensive care and ventilator capacity along with public health contact tracing capacity and resilience. The third grouping includes findings that countries that who had comprehensive and effective test, trace and isolate programmes throughout the first wave tended to have lower levels of excess deaths or those who did not but implemented nationwide lockdowns at earlier stages of their respective epidemics. From the UK’s perspective, these three factors appear to have combined to provide the perfect storm, for Covid-19 to demonstrate how frail and vulnerable our economy and society is to the nation’s ill-health.

As countries around the world enter the second wave and with the seasons against us, this analysis provides several insights for policy makers. Governments, industry and society generally have had several months to plan for this second wave, our testing capacity has increased exponentially, while treatment pathways have been enhanced. The next six months will provide many challenges and we expect further excess deaths over this period; how the total mortality and morbidity impacts of the pandemic fall across populations will have long lasting implications for the public’s health, health services and the economy for years to come.

At LCP, our health analytics approach leverages the increasing availability of data and our cutting-edge modelling approaches to put timely actionable data in the hands of key stakeholders, bringing clarity to decision makers across healthcare and life sciences.