2021-10-06 General – Pandemic in British Columbia

Mitigation Measures

This article says that the Government of Canada has come out with new vaccine mandates. All federal employees — including those who work from home or in a different country — have until 29 October to get vaccinated. Everyone over 12 must be vaccinated to take a plane or train inside Canada.

Transmission

This study looked at aerosol exhalation while doing various breath-related activities (e.g. talking, shouting) while undergoing various common respiratory therapies (e.g. breathing from a high-oxygen tube).

Here’s the data on how much worse various activities are than quiet breathing:

I was surprised that shouting expels almost three times more aerosol than exercising, and that even talking expels 35x more particles than breathing quietly. And yeah, coughing is really bad.

They found that the various therapies also increased aerosols, though not by as much as the activities did. For example, high-flow nasal oxygen increased particle counts 2.3x during quiet breathing.

Unsurprisingly, facemasks decreased the aerosol count, though by less than I had expected.

Variants

This study from Ontario says that Delta is more severe than COVID Classic: 108% higher infection risk, 235% higher hospitalization risk, and 133% higher ICU risk.

Vaccines

This study in six different states in the USA found that Comirnaty:

is very effective at 16 weeks (81% one dose / 91% two dose),
for those who got infected, the viral load was 40% lower in vaxxed people than unvaxxed,
the vaxxinated spent 2.3 fewer days in bed.

This study in Israel found that in health care workers vaxxed with Comirnaty found:

levels of neutralizing antibodies that fell relatively quickly for the first three months, then waned more slowly;
after six months, levels were
- lower in men than women
- lower in people over 65 than those younger
- lower in immunosuppressed people than non-immunosuppressed.

Remember that Israel used a short interval between dose1 and dose2.

This study of Comirnaty in Qatar found that:

the effectiveness against infection was 36.8% after dose 1 / 77.5% after dose 2;
effectiveness declined gradually for three months and then accelerated, falling to ~20% in months 5 through 7 after the second dose.

Note that the Beta strain dominated in Qatar before Delta took over. This is a bit different from most other places, where Alpha dominated before Delta took over. Beta is not as transmissible as Delta, but it’s more vax-evasive.

This study in Israel of myocarditis in people vaccinated with Comirnaty found:

52 people out of 2.5M developed myocarditis, or 2.13 per 100,000;
the highest incidence (10.69 per 100,000) was in males between 16 and 29;
76% had mild symptoms, 22% had intermediate symptoms, and 1 person had severe symptoms;
one patient died after leaving the hospital of unspecified causes, but nobody else died;
of 14 patients who had left ventricular dysfunction on echocardiography during admission, nine recovered either before they left the hospital or after followup. (I don’t know about the other five.)

A different study in Israel of myocarditis in people vaccinated with Comirnaty had similar findings, although they had one fatality (out of 136 myocarditis patients).

This study of myocarditis in Southern California found:

an incidence of 8 cases per 100K from first doses and 58 per 100K from second doses;
roughly half had gotten Comirnaty and half had gotten Spikevax;
all myocarditis patients were men, with a median age of 25;
everybody got all better.

Long COVID

This large study in the USA found that people who had survived COVID-19 had significant incidence of circulatory system problems a year later, including 1.48x risk of stroke, 1.79x risk of atrial fibrillation, 1.48x risk of acute coronary disease, 1.73x risk of heart failure, etc. NOT GOOD. DON’T GET COVID-19. GET VACCINATED.

Other

This isn’t COVID-19, but it is so f awesome! There’s an effective malaria vaccine! Finally!