Cumulative deaths by country, plotted against number of days since 10th death occurred; graphic by John Burn-Murdoch for UK FT.

This is the fourth in a series of articles about the current pandemic, drawing on the best available science and data we currently have at our disposal. The previous articles:

1. What’s Next for CoVid-19 (a snapshot at Mar 29, 2020 as deaths started to soar)
2. CoVid, Complexity & Collapse (the larger context as at Apr 5, 2020)
3. The Least We Can Do (what we’ve learned and what we can do, as at Apr 15, 2020)

This article updates the above by describing some new learning about this virus that might dramatically change what happens now, and the courses of sensible action open to us. Sources include former infectious disease expert Dr Michael Greger’s videos, and summaries from recent science journals.

So here we go: Ten things even most experts didn’t know a month ago:

1. The mortality rate for the virus, so far, looks to be more like 0.2% of those infected than the 1% experts initially expected. The reason for the large error is that we didn’t realize how many were actually, apparently, contracting the disease asymptomatically, and how many would recover without treatment or not even show symptoms, thanks mainly to a near-global lack of testing capacity that led to utter uncertainty about the mortality rate and who was infected. We now have a slightly better idea, principally from the number of deaths and hospitalizations (still a very rough number, but much more useful than positive tests when so few have been tested and so many are asymptomatic). The consequences of this 0.2% rate, if it’s correct (and some small-scale intensive testing studies suggest it is), is that this virus in its first wave will probably kill only about 1-2 million worldwide, which is about three times the annual number of deaths from “regular” influenzas in recent years. It also suggests that five times as many as suspected have actually contracted the disease, perhaps 10% of the global population, and perhaps twice that proportion in Europe and North America, without serious incident. That still leaves the vast majority vulnerable to infection when containment measures are relaxed, and to the next wave(s) of the pandemic, but still means five times as many people have acquired or have natural immunity than most experts expected.
2. There are six coronaviruses known to affect humans, of which four are endemic “common cold” viruses. You’ve almost certainly had them. The problem with these coronaviruses is that, unlike HxNx type flu viruses, these coronaviruses only confer immunity on those infected for an average of 45 days, after which you can get them again. So the hopes for eventual permanent “herd immunity” to CoVid-19 may be wishful thinking; we might see cases recur and spike until a reliable vaccine has been developed and almost universally given to humans. This is a highly contagious disease, perhaps five times more than we’d thought, and a small minority un-inoculated could wreak havoc.
3. Infection with coronaviruses can have serious and lasting, debilitating effects on its victims, even those who seem to have fully recovered. These viruses, and our immune systems’ “cytokine storm” reactions to them, can leave tissues and organs severely damaged and susceptible to later organ failure or other infections, and to neural, psychological and brain damage. We may not know for years.
4. There has not been a single confirmed case of anyone getting CoVid-19 from delivered groceries or other packaging. That’s not to say there is no risk, but compared to the risks of shaking hands or being near a cough or sneeze, they are hardly worth worrying about.
5. Masks work, but not so much to prevent the virus from being transmitted to the wearer; they do significantly reduce the risk that you, if you are unknowingly infected, will transmit it to others, or that you will touch your eyes, nose or mouth with an infected hand, and hence give the virus its needed passage to your own throat and lungs. For the same reason, gloves are less important than masks in preventing disease spread (they can carry the virus much as your hands do).
6. You are most infectious before you show any symptoms. That’s why our lack of preparedness, and hence shortage of test kits, allowed the disease to spread so far so fast. In most countries, you couldn’t even get a test, and were assumed uninfected, unless you showed symptoms.
7. Although the science is not yet certain, so far it seems unlikely that you can contract the virus through skin lesions (or otherwise through your skin) or through sexual or anal transmission. However, since the virus can pass through to feces and end up in aerosol spray from flushed toilets, you should close the lid before you flush public toilets.
8. Pangolins, a kind of anteater and the likely intermediary for the coVi-19 virus from bats to humans, are the most trafficked animal in the world. They have been hunted nearly to extinction both as a ‘delicacy’ for humans and as a source for ‘cures’ in ‘traditional Chinese medicine’. China has now banned their consumption but not their ‘medicinal’ use.
9. There is no need to use hot water when washing your hands for 20 seconds or more with soap.
10. It bears repeating that the second wave of the 1918 influenza, in some reckonings the biggest killer of humans in history, resulted from a fast and dramatic mutation that shifted the most vulnerable victims from the old and immune-suppressed, to the young with the strongest immune systems(who mostly died due to ‘cytokine storm’ responses from their own immune systems). Average age of victims shifted from about 60 (first wave) to about 30 (second and most virulent wave).

It should also be noted that vaccines are not panaceas — as I’ve written elsewhere, viruses are not our enemies, but essential parts of every ecosystem. And vaccines don’t guarantee 100% immunity. As we continue to crowd farmed and exotic animals into ever-more confined and crowded spaces, and then eat them, the recent explosion of new viruses and mutations is very likely to outstrip our capacity to develop vaccines (as is already starting to happen with ‘regular’ influenza vaccines).

What’s more, there will always be a horde of rabid anti-vaxxers ready to sabotage vaccine programs any way they can, and refuse to inoculate themselves, to everyone’s peril (read Eula Biss’ brilliant book On Immunity for the full extent of this challenge). Viruses are particularly adept at mutation, and we could soon find ourselves in a never-ending and hopeless race to try to keep ahead of the mutations, precisely when they are getting cleverer, as we provide them more fertile breeding grounds, at adapting to our vulnerabilities.

For a brief but comprehensive summary of everything we know right now, please read this.