Coronavirus thread

[Doug]

I liked this article that commented on the recent mask study as a counterpoint...

"It's unclear to me whether they actually measured respiratory droplets," said William Ristenpart, a professor of chemical engineering at the University of California, Davis who was not part of the study. Instead, the Duke team may have measured dustlike particles of fabric that came from the masks. "Research from my group in peer review right now indicates that some fabrics shed substantial numbers of particulates that confound mask efficacy measurements," Ristenpart told Live Science.


https://www.livescience.com/coronavi...k-gaiters.html

[RoyGBiv]

I sometimes think we should say that drug companies can sell their product for whatever they like (so they can cover R&D) but must sell it for the same price to all comers (with maybe some things like volume discounts). There is no reason that, say, the Canadian gov't ought to be paying less than Medicare does.

If we want to sell at the marginal cost of production as charity to very poor countries, OK, call it foreign aid. But all first world countries ought to be paying the same.

This would be very simple to write into a contract when you're handing out development money.

[UNM1136]

Just finished my two weeks of monitoring after a potential exposure. Body temp rose alarmingly a couple of days, but was not consistent, and never hit the magic number. (99.7 a couple of days, no higher, no other symptoms). Now just another 5.5 months of blood tests for HIV, and to a lesser extent Hep, since my titers for Hepatitus are still showing likely active immunity.

pat

[Wondering Beard]

Covid Spread Can’t Only Be Explained by Who’s Being ‘Bad’


"The mainstream narrative is that it’s all about good behavior when cases go down — mask wearing and giving up our social lives for the greater good. And conversely, bad behavior must be what makes them go up. We talk about certain regions having the virus “under control,” as if falling cases are purely a matter of will-power. A sort of moral reasoning is filling in for evidence.

But why, then, have cases plummeted in Sweden, where mask wearing is a rarity?"



“The issue with data is one can manipulate it to show anything you want if you have an agenda,” says YouYang Gu, an independent data scientist. Cherry picking is easy — prediction is much harder, and Gu is getting some attention for the fact that models he’s been creating since April actually forecast what’s happened with the spread of the disease in the U.S."


"But scientists have little experience applying herd immunity to a natural infection, and what understanding they have is changing. Scientists have started to investigate the possibility that there’s another critical factor here — heterogeneity in the way humans interact, and in our inherent, biological susceptibility to this disease."


"Those differences can inform disease models, says statistics professor Gabriela Gomes of the University of Strathclyde in Scotland. “What we see is that infections do not occur at random, but that people who are most susceptible to infection get exposed first,” she says, leaving a pool of ever-less susceptible people behind."


"She says she didn’t expect to come up against resistance to her models in the scientific community. While she’s starting to get some attention in the media, she said journal editors told her that her modeling ideas, in preprint, posed the danger of making people feel entitled to relax their vigilance. Maybe the opposite is true, she suggests. Maybe censoring all but the most pessimistic views could discourage action by making the problem seem endless."

[TDA]

Covid Spread Can’t Only Be Explained by Who’s Being ‘Bad’

"She says she didn’t expect to come up against resistance to her models in the scientific community. While she’s starting to get some attention in the media, she said journal editors told her that her modeling ideas, in preprint, posed the danger of making people feel entitled to relax their vigilance. Maybe the opposite is true, she suggests. Maybe censoring all but the most pessimistic views could discourage action by making the problem seem endless."

It just so happens that I have a copy of The Diffusion of Innovations propping up my laptop right this second. One thing scholars have known for decades is that people don't do a damned thing because of findings published in scholarly journals. Of course that's the only place they print their findings, so even most scholars still don't know.

[SiriusBlunder]

Scientists say Hong Kong man got coronavirus a second time

University of Hong Kong scientists claim to have the first evidence of someone being reinfected with the virus that causes COVID-19.

Genetic tests revealed that a 33-year-old man returning to Hong Kong from a trip to Spain in mid-August had a different strain of the coronavirus than the one he’d previously been infected with in March, said Dr. Kelvin Kai-Wang To, the microbiologist who led the work.

The man had mild symptoms the first time and none the second time; his more recent infection was detected through screening and testing at the Hong Kong airport.

“It shows that some people do not have lifelong immunity” to the virus if they’ve already had it, To said. “We don’t know how many people can get reinfected. There are probably more out there.”

[Nephrology]

Scientists say Hong Kong man got coronavirus a second time

If he is (and remains) asymptomatic I am not necessarily too worried about that. That would suggest that exposure to COVID protects you against disease with re-infection.

[SiriusBlunder]

If he is (and remains) asymptomatic I am not necessarily too worried about that. That would suggest that exposure to COVID protects you against disease with re-infection.

Yep, there was someone in the article that pointed that out, so possibly good news.

Another questioned if a reinfected person would be an asymptomatic carrier and infect others. Any thoughts on that?

[Erik]

Posted upthread, but a good friend of mine knows two people who had it twice, one of whom gave it to his wife the second time (who died from it).

[pangloss]

Yep, there was someone in the article that pointed that out, so possibly good news.

Another questioned if a reinfected person would be an asymptomatic carrier and infect others. Any thoughts on that?

What you're asking about reduces to two main numbers, or possibly three. The first is how much virus is in the respiratory tract, i.e. how much virus the person sheds. It stands to reason that if you don't have very good immune control of the virus, presumably in a primary infection, that you'll make a lot of virus. The second time you see the virus and you have some immunity to it, you'll make less virus because of the immune response killing virus and infected cells. The second number is the duration of shedding, or how long a person is contagious. Start lopping days off that time period and your chances of infecting someone else go down quickly. The potential third number is behavioral. If you're sick and you feel sick, you are more likely to stay home. If you're infected and you don't feel sick or perhaps just mildly ill, you'll be more likely to go out and mix with other people thereby increasing your chances of infecting someone else.

I expect that people with near subclinical infections will be able to transmit the infection to others but at a significantly lower rate than during their first infection with the virus. There are lots of respiratory viruses that re-infect people: respiratory syncytial virus, metapneumovirus, and other coronaviruses. There's no reason to expect this one to be any different.