These notes date from 2020 and are retained as written. They reflect the information available at the time and are not current clinical guidance.
A virus expresses itself through the host
Everyone is eventually exposed. A virus lacks morality and politics; it expresses itself according to the host’s biochemical capacity. That framing was the reason for arguing, in 2020, that metabolic health was a modifiable determinant of outcome rather than an irrelevance during an acute crisis.
Given that fewer than 12.2% of US adults were metabolically healthy in 2009–2016 and fewer than 7% are today, the size of the susceptible population was not a marginal consideration.
What the tests measure
PCR detects viral genetic material and answers whether virus is present now. IgM antibodies rise early in an immune response. IgG antibodies rise later and persist, indicating past exposure. They answer different questions, and using one to answer another’s question produced much of the confusion of that period.
Ventilator design
An observation from anesthesia practice: hospital workers may have faced higher exposure partly because ICU ventilators are open-loop systems, unlike the closed-loop circuits used in anesthesia. The distinction is about where exhaled gas goes.
Why it is kept
This is archived rather than removed because the underlying argument — that host metabolic capacity shapes the expression of an infectious exposure — did not depend on the specifics of that virus, and has held up better than most of what was said at the time.
