Flu and pneumonia were mentioned more times than Covid-19 on death certificates in England and Wales during the first two years of the pandemic, new analysis shows.

But Covid-19 was identified as the underlying cause of death in more than four times as many deaths as flu and pneumonia during the same period – reflecting how the virus has taken a far greater direct toll on the population.

The findings have been published by the Office for National Statistics (ONS) and are the first detailed attempt to contrast Covid-19 and flu as causes of death over the course of the pandemic.

Deaths due to flu & pneumonia registered each week in England & Wales
(PA Graphics)

There are limitations to making direct comparisons, as death certificates are likely to underestimate flu deaths because not all patients are tested for it, the ONS cautioned.

It is possible to identify trends in the figures and the “approximate mortality” associated with each cause, however.

Covid-19 was the underlying cause of 73,766 deaths in England and Wales in 2020 and 67,258 deaths in 2021.

The last time that deaths due to flu and pneumonia reached similar levels was 1929 (73,212 deaths), while the most severe outbreak on record occurred in 1918, the year of the “Spanish flu” pandemic (172,149 deaths).

An average of around 43,000 people died due to flu and pneumonia each year during the 20th century, but since 2000 – when widespread vaccination was introduced – the figure has dropped below 30,000.

This fell to 19,464 in 2020 – the lowest since 1948 – and then again to 16,237 in 2021, a decrease that “could be linked to restrictions that limited social contact”, the ONS said.

Deaths due to flu and pneumonia in both the winter of 2020/21 and 2021/22 “remained well below levels seen before the Covid-19 pandemic” and “it is possible that lockdowns and measures such as social distancing put in place to curb the spread of coronavirus also reduced the spread of flu compared with previous years”.

(PA Graphics)

There were more than four times as many deaths in England and Wales due to Covid-19 between March 2020 and April 2022 (148,606) than due to flu and pneumonia (35,007).

But a different picture emerges when looking at deaths where Covid-19 was mentioned anywhere on somebody’s death certificate, either as a leading cause or contributory factor.

Some 170,600 of these deaths were registered in England and Wales in the first two years of the pandemic, compared with 219,207 deaths that mentioned flu and pneumonia.

This reflects the fact that flu also causes increases in deaths due to other conditions, such as cardiovascular diseases.

While coronavirus has been mentioned on fewer death certificates since the pandemic began, it is far more likely to have been listed as the underlying cause of death.

It is not possible to say for certain from the data available whether Covid-19, flu and pneumonia are “behaving in similar ways”, the ONS added.

“Infection and antibody levels, vaccination rates, restrictions and lockdowns, and differences between variants all affect the data we have on Covid-19 mortality.

“Some of these factors also have affected flu and pneumonia deaths over the same period, meaning the data we have so far is quite atypical.

“Deaths due to Covid-19 remain higher than deaths due to flu and pneumonia, although deaths due to Covid-19 seem to be decreasing, while deaths due to flu and pneumonia are at historic lows and seem to be rising. We will continue to monitor the data closely.”