Explaining the lag between cases, hospitalisations and deaths during the Coronavirus pandemic, and why the time to act is always four weeks ago.


First published in January 2021.


A picture via the Simple Covid app to explain why we are in so much trouble:

  • When cases RISE, hospitalisations rise 7 days later, and deaths ~10 days after that.
  • When cases FALL, we won’t see declines in admissions for 7 days, and deaths ~10 days after that.
The natural time course of Covid. | SimpleCovid.org

These are the cases.

The time from exposure to symptoms is around 5-7 days, so these patients were all exposed a week ago.

This rise is very concerning – as hospitalisations and deaths will inevitably follow the same trend.

Current Covid-19 cases.

These are the current hospital inpatients.

These people were ALREADY exposed two weeks ago (see above).

This trend continues upwards for ANOTHER TWO WEEKS at least, if we do nothing today. Every day we wait adds on to that other end.

We are ALREADY above the Spring peak.

Current hospital inpatients.

Here is deaths within 28 days – patients here were exposed 3-4 WEEKS prior.

Again, this trend continues upwards for another 3-4 weeks AT LEAST from today. Again, if we do nothing, it keeps rising further.

We won’t see the effect of Christmas here until the end of January.

Covid-19 deaths within 28 days.

So this is why we seem to be always WEEKS behind the virus, because WE ARE.

Which is why we always need to act BEFORE we see the deaths, if we actually want to avert them.

The natural time course of Covid. | SimpleCovid.org

Lastly, what happens if we can only get the R to 1?

When R=1, the virus continues at the same rate it was before, every day.

  • 5,000 cases/day > Restrictions > R=1 > 5,000 cases every day.
  • 50,000 cases/day > Restrictions > R=1 > 50,000 cases every day.

And same RESTRICTIONS in both examples.

With the new variant, it might be much harder to get the R below 1.

If we only get R=1, then whatever the time-point we hit that FREEZE button is where we get stuck – until we can vaccinate and get R below 1 again.

The longer cases rise, the higher that number will be. And the higher the daily hospitalisations and deaths will be.

There is a critical upper limit to what hospitals can physically handle. Once we reach that, we start running out of beds, staff, oxygen, ICU care. We are already near. When that happens, deaths go UP even further.

So, the time to act is ALWAYS four weeks ago, and the next best time is NOW.

So, we need a national lockdown, TODAY.🔷




Dr Dominic Pimenta, Doctor. Writer. Researcher. Chairman of HelpThemHelpUs.co.uk. Active NHS campaigner.





[This piece was first published as a Twitter thread and turned into the above article on 3 January 2021 with the purpose of reaching a larger audience. It has been minorly edited and corrected, and published with the author’s consent. | The author of the tweets writes in a personal capacity.]

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