Going Viral
On
The situation with the coronavirus formerly known as Wuhan, then 2019-nCoV and now COVID19, is developing rapidly. The picture is becoming clearer and more nuanced, I think, and initial obfuscation by the CCP MAY be changing for the better.
On the one hand, the virus might be more infectious than was originally believed.
A paper in pre-print at MedRxIV (ie not yet peer-reviewed) has data that gives a value between 4.7 and 6.6 (1). This is not entirely surprising. The reported incubation period is continually extending, and is now considered to be up to 14 days (2). Isolated cases suggest it may extend as far as 24 days (3), but this paper is also in pre-press and according to the W.H.O. it may reflect second exposure. Added to this is the ability of the virus to survive ex corpore (ie on door handles and work surfaces) which, if it behaves like other coronaviruses, may be up to 9 days or even 28 days at lower temperatures (4). For Howard Hughes enthusiasts, hydrogen peroxide is effective at disabling coronaviruses on surfaces at a concentration of 0.5% and an application time of just 1 min (4).
But what about virulence? How dangerous is Covid19?
The data coming out of China are still very confusing. The Chinese have made astonishing progress in the area of communicable disease control in the last half century, and their improvements in life expectancy and their stellar growth rates in the last three decades reflect this (5);but the tendency of the CCP to put nationalism and politics ahead of public health at critical moments (6)may have made containing COVID19 more difficult than it should have been.
While the reported fatality rate is still hovering around 2% (3), the unprecedently extensive quarantine process now in place in many regions of China, the militarization of the public health response and some local reports continue to suggest that the true figures may be higher. And the virus is clearly on a world tour. So should we be scared?
We should be concerned, certainly, but maybe we are not quite as much at risk as the Chinese.
It is beginning to look as if the key risk factors that predispose to serious illness include immunisationagainst (or previous exposure to) any other coronavirus (7), smoking, and the presence of a target protein in certain cells of the lungs called angiotensin 1 converting enzyme 2, or ACE2 (8).
(ACE2 has several functions. In the artery walls it is involved in the control of blood pressure, which is why ACE inhibitor drugs are used as antihypertensive agents. It is not clear what ACE does in the lungs, but its presence there may explain the tendency of ACE inhibitors to cause persistent cough and bronchospasm).
Previous exposure to a coronavirus is almost universal (9). However, the Chinese smoke like we used to in the 50’s, and there is preliminary evidence that smoking increases the expression of ACE2 in their lungs (10, 11); so they could be, as a group, more at risk than we are.
The usual recommendations to keep from being infected (wash your hands, avoid sick people etc) don’t seem to work very well against the new coronavirus. This could, however, be a good time to give up smoking and probably all forms of nicotine.
If smoking is a significant contributor to virulence, therefore, it may be that the public health problems posed by COVID19 within China will not be so extensive outside of China. I would warn against complacency, however. The situation would be changed, completely, by recombinant COVID19 / H5N1, ie a viral strain which combined high transmissibility with high virulence. This would be a public health disaster, and a major discontinuity.
As H5N1 is causing problems, right now, and almost next door to Wuhan, this scenario cannot yet be ruled out.
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