Bits and pieces from a news article that summarizes recent scholarly studies.

Some  moderately good news, and a reminder that increased testing means finding more cases, and finding them earlier, which means people get medical treatment sooner. (More testing means less suffering and fewer deaths. For those of us who care about such things.)

Over the course of the pandemic the death rate in people diagnosed with COVID-19 (the case-fatality rate) has declined.

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The most encouraging reason for the decline is the steep learning curve of knowing how to treat those who are seriously ill with COVID. Doctors have learned through direct experience how to better manage COVID patients, and many interventions became standard practice between March and August. For example, it is better to rest patients on their stomach than their back, and it is better to delay ventilation as long as possible. The discovery that steroids can reduce the risk of cytokine storm was perhaps a significant improvement. Some patients now get convalescent plasma, something that obviously could not have happened early on.

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If, for example, you social distance and wear a mask but still get sick (it’s possible, because these protections are not perfect, people do not completely adhere to them, and the virus is very contagious) you will likely get a lower initial viral load than someone who was hugging someone, without a mask, who was infected. What the study found was two things – that the initial viral load correlates with the risk of death, and that as the pandemic progresses people are presenting with a lower viral load on average. So protective measures seems to be shifting to lower exposure, so many people do not contract the virus and those that do will tend to have lower viral loads. This will tend to generate lots of milder cases, some of which will be diagnosed and even admitted to hospital but have a lower fatality rate.

This study also finds that there is likely a significant effect from earlier diagnosis. We are doing more testing than in March, which means some people will be diagnosed at an earlier phase of their illness, be treated earlier, and have better outcomes. This is a good thing, and is another reason to have aggressive testing – to prevent spread of the virus, but also to treat people early. —COVID-19 Becoming Less Deadly