2022-03-10 General

Mitigation Measures

This paper reports on a big study in the US which compared school districts which had mask mandates with those that did not. For every 100 community-acquired cases, districts with universal mask mandates had 7.3 infections, while districts with optionally masks had 26.4. Don’t let anybody tell you that masks don’t work


This article talks about wastewater surveillance. It mentions that New York sees some unseen variants in its wastewater(as I mentioned on 3 Feb 2022), but apparently there have been unseen variants in St. Louis MO, California, and Wisconsin.

Interestingly, the St. Louis unseen strain disappeared after six weeks. That suggests to me that it was one person.

On 3 Feb 2022, I mentioned that the New York strains didn’t seem to move around, which was strange because people move around. But recently I’ve been thinking about that: since the pandemic started, I haven’t move around a lot. I’ve been thinking about it, and I think that I’ve only used a toilet in Canada outside of the city of Vancouver less than seven times, with around another ten times inside Vancouver but in different neighbourhoods. I am a scaredycat, but I am not immunocompromised: if I were immunocompromised, I probably would have gone out even less often.

Furthermore, fecal matter sheds more virus than urine. It is quite possible that I never made fecal deposits in outside Vancouver. There are some people I have known who make a deposit first thing in the morning and then almost never made an additional deposit as the day goes on. So it is now more plausible to me that the novel variants that New York is seeing come from people.

The article talks about how difficult it is to interpret the signals, since some sewage pipes get rainwater in them, so heavy rain will dilute the concentration. Well, it turns out that there are some viruses which circulate commonly that they can use as references. One reference is a virus which infects peppers but goes right through humans without bothering them, the pepper mild mottle virus (PMMoV). They can compare the amount of SARS-CoV-2 to the amount of PMMoV to get a better estimate of the amount of SARS-CoV-2 that is in the community.

And if you have been taking heart in the Lower Mainland wastewater graphs showing that the amount of SARS-CoV-2 in the water has almost gotten down to Oct/Nov levels? Alas, this article says that the amount of SARS-CoV-2 in Omicron-infected people is lower than in people infected with different strains, perhaps by a factor of two or three. 🙁

From the BC CDC Week 8 Situation Report (ending 26 Feb):


This paper (from January 2022) found that 43% of the people who had Long COVID with cognitive issues had the cognitive issues show up after at least a month, and this was associated with younger age. 29% of those with cognitive issues said it showed up after two or more months.

Here is chart from a different paper (from Dec 2020) by the same team which shows the onset time for various symptoms, as discussed in this tweet:



Quick review: antibodies are things which stick to a pathogen. Sometimes the antibodies just signal to the T cells, “HEY! COME EAT THIS!” Other times, they mess with the mechanical function of the virus.

Monoclonal antibody treatments are infusions filled with one or sometimes two different antibodies which are good at sticking to the virus and/or messing with its mechanical function.

This preprint‘s study had really good luck with a thingie (which they called a “bispecific antibody”) which is basically a string (or maybe a rod?) holding together two different antibodies, named n3113v and n3130v. It worked better than having a mix of free-floating n3113v mixed with free-floating n3130v. I didn’t completely understand the paper, but I gather that the combined molecule held the SARS-CoV-2’s jaws open wider than SARS-CoV-2 needed it to be in order to get into the cell.

The study also found that they could deliver the bispecific antibody nasally to hamsters, and that it went to the respiratory tract better than an injected vaccine.

Live Attenuated Virus

This article (from Nov 2020) found a very striking inverse correlation between antibody titres against mumps and COVID-19 severity.

Recommended Reading

The article on wastewater treatment that I mentioned above is worth reading.