How Deadly is Covid? ... Does Policy Reflect it? - Granite Grok

How Deadly is Covid? … Does Policy Reflect it?

How Deadly is Covid?

When the World Health Organization (WHO) said in early March about 3% of people who get COVID die from it, they were wrong by at least one order of magnitude. The COVID fatality rate actually has turned out to be between 0.2% – 0.3%.

The reason for the highly inaccurate early estimates is simple. We were not identifying most of the people with COVID infections.

Computation of “case fatality rate” equals  (number of deaths)/(total number of confirmed cases). To obtain an accurate fatality rate, the denominator should be the number of people who have been infected.

What we did then

In March, only the people who became sick enough for hospitalization were “cases” but the majority of people with COVID have very mild or no symptoms. These people were not in the count in the early days. The result was a highly misleading fatality rate that drove public policy and continues to sow fear and panic. People still hold a perception that resulted from misleading data in March.

So, how do we get an accurate fatality rate? We test for seroprevalence. The big word means we test to find out how many people have evidence in their bloodstream of having had COVID. This is easy with some viruses.

Anyone who has had chickenpox still has that virus living in them. It stays in the body forever. COVID, on the other hand, like other coronaviruses, doesn’t stay in the body. Someone who gets COVID infection and then clears it will be immune from it, but it won’t still be living in them.

So, what we need to test for are antibodies or other evidence that someone has had COVID. Even antibodies fade over time. This means testing for them still results in an underestimate of total infections. How deadly is covid?

What we have learned

Seroprevalence was in development in the early days of the epidemic. In April, a series of studies using antibody tests were done. From the results, researchers were able to determine how many people in California’s Santa Clara County had had covid. At the time, case identification was about 1,000 COVID cases in the county.

The antibody tests found infection of 50,000 people current and past tense. This means there were 50 times more infections than identified cases. This was enormously important. It told researchers the fatality rate was not 3%. It was actually closer to 0.2%. For illustration; Deaths were not three in 100, but two in 1,000. How deadly is covid?

When it came out, this Santa Clara study was controversial. The way science tests controversial studies is to see if they can be replicated. Today there are now 82 similar seroprevalence studies from around the world. The median result of these 82 studies is a fatality rate of about 0.2%. That’s what was found in Santa Clara County.

In some places such as NYC, the fatality rate was higher. It was more like 0.5%. In other places like Idaho, it was lower. It was more like 0.13%. This variation shows us the fatality rate is not simply a function of how deadly a virus is.

Mistakes were made, we know better now, policy should change

The fatality rate is a function of who gets covid and of the quality of the health care system. In the early days of the virus, our health care systems managed COVID poorly. Part of this was due to ignorance. We used very aggressive treatments such as the use of ventilators. In retrospect, this may have been counterproductive. Part of it was due to negligence. In some places, we allowed a lot of people in nursing homes to get the virus.

How deadly is covid? Bottom line; the COVID fatality rate is known to be about 0.2%. The policy should reflect the change in our knowledge of the severity of the disease.