The biology of coronavirus COVID-19 - including research and treatments

Jonathan Edwards said:
That sounds cogent. The pangolin virus might have got played with or there might be coincidence but the simplest explanation looks plausible. Might be good news for pangolins.
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Perhaps it is a novel bat virus, evolved through zoonotic transmission to pangolins (recombination with some pangolin virus components) and back?
 
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Sasha said:
@Jonathan Edwards - is this likely to be a safe treatment, in the sense of the plasma (or antibodies or whatever, if anything, they're extracting from it) not carrying other infections?
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The FDA issued approval for "Investigational COVID-19 Convalescent Plasma - Emergency INDs" on March 24th.
https://www.fda.gov/vaccines-blood-...l-covid-19-convalescent-plasma-emergency-inds
COVID-19 convalescent plasma must only be collected from recovered individuals if they are eligible to donate blood (21 CFR 630.10, 21 CFR 630.15). Required testing must be performed (21 CFR 610.40) and the donation must be found suitable (21 CFR 630.30).

Additional considerations for donor eligibility should be addressed, as follows:
  • Prior diagnosis of COVID-19 documented by a laboratory test
  • Complete resolution of symptoms at least 14 days prior to donation
  • Female donors negative for HLA antibodies or male donors
  • Negative results for COVID-19 either from one or more nasopharyngeal swab specimens or by a molecular diagnostic test from blood. A partial list of available tests can be accessed at https://www.fda.gov/medical-devices...-medical-devices/emergency-use-authorizations.
  • Defined SARS-CoV-2 neutralizing antibody titers, if testing can be conducted (e.g., optimally greater than 1:320)
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Sajadi et al. Temperature, Humidity and Latitude Analysis to Predict Potential Spread and Seasonality for COVID-19.

Thought this was interesting. The authors write: "The distribution of significant community outbreaks along restricted latitude, temperature, and humidity are consistent with the behavior of a seasonal respiratory virus."

upload_2020-3-26_22-16-14.png

Another study by Wang et al. suggested that high temperature and high humidity reduce the transmission of COVID-19.

Might be a bit of wishful thinking but I'm still hoping that the virus will be less virulent in the summer months.
 
Michiel Tack said:
Thought this was interesting. The authors write: "The distribution of significant community outbreaks along restricted latitude, temperature, and humidity are consistent with the behavior of a seasonal respiratory virus."
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I hope that chart is telling the correct story (and that warmer temperatures limit community outbreaks). Unfortunately I suspect that it might just be that the identified community outbreaks are where there are more medical services and governments communicating more transparently in the early stages of an outbreak.

See for example this report in the Guardian about Indonesia:
Indonesia’s hidden coronavirus cases threaten to overwhelm hospitals
The country already has the most deaths in south-east Asia, but research suggests the official 800 infections so far may only be 2% of the total
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It was just last month that Indonesia’s coronavirus cases stood at zero, with officials fiercely rejecting suggestions that infections were spreading undetected.
Weeks later, 78 fatalities have now been linked to the virus, the highest number in south-east Asia. Seven health workers are among those who have died.
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Any advantage offered by warm humid weather can be negated by other factors, like poor government responses, inadequate healthcare systems, and other factors, like large numbers of people living in close proximity.

Sadly, Indonesia has all those factors in play. I fear they are going to pay a particularly high price. :(
 
Hutan said:
I hope that chart is telling the correct story (and that warmer temperatures limit community outbreaks). Unfortunately I suspect that it might just be that the identified community outbreaks are where there are more medical services and governments communicating more transparently in the early stages of an outbreak.
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Indeed.

I worry about the most densely populated developing countries like India and Bangladesh!
 
Preprint (not peer reviewed), open access
https://www.medrxiv.org/content/10.1101/2020.03.11.20031096v2


Relationship between the ABO Blood Group and the COVID-19 Susceptibility
Jiao Zhao (and many more), 27 March 2020

Abstract

The novel coronavirus disease-2019 (COVID-19) has been spreading around the world rapidly and declared as a pandemic by WHO. Here, we compared the ABO blood group distribution in 2,173 patients with COVID-19 confirmed by SARS-CoV-2 test from three hospitals in Wuhan and Shenzhen, China with that in normal people from the corresponding regions. The results showed that blood group A was associated with a higher risk for acquiring COVID-19 compared with non-A blood groups, whereas blood group O was associated with a lower risk for the infection compared with non-O blood groups. This is the first observation of an association between the ABO blood type and COVID-19. It should be emphasized, however, that this is an early study with limitations. It would be premature to use this study to guide clinical practice at this time, but it should encourage further investigation of the relationship between the ABO blood group and the COVID-19 susceptibility.
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Chinese study on Chinese patients - blood group distribution differs by ethnicity; wikipedia lists 4 different ethnicities within China (https://en.wikipedia.org/wiki/Blood_type_distribution_by_country) but my geography is too poor to know if this is relevant for the cohorts in this study.

Just my luck: I'm an A.
 
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Ravn said:
Relationship between the ABO Blood Group and the COVID-19 Susceptibility
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It's amazing, considering how many blood tests I've had over the years, that I have no idea what my blood type is. Looking over the blood test reports, not one of them indicates blood type.

I imagine it's a special test, which may not have much utility unless you need a transfusion. I'm sure that you get blood typed if you go into the military, and it goes on your dog tags, for obvious reasons.
 
Hutan said:
I suspect that it might just be that the identified community outbreaks are where there are more medical services and governments communicating more transparently in the early stages of an outbreak.
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Comment on this by O' Reily et al. Effective transmission across the globe: the role of climate in COVID-19 mitigation strategies. https://cmmid.github.io/topics/covid19/current-patterns-transmission/role-of-climate.html

The authors write:
All WHO regions have at least six countries with confirmed local transmission, effectively spanning all climatic zones, from cold and dry to hot and humid regions. Notably, countries reporting local transmission include Malaysia, the Philippines, Indonesia and Thailand, with much movement between them and China. However other countries outside of Asia including Burkina Faso, Democratic Republic of Congo, Panama and Paraguay, with mean ambient temperatures between 1 January 2020 - 14 March 2020 greater than 25°C (Figure 1B) also report local transmission.

The ability of SARS-CoV-2 to effectively spread globally, including in warm and humid climates, suggests that seasonality cannot be considered a key modulating factor of SARS-CoV-2 transmissibility. While warmer weather may slightly reduce transmission of SARS-CoV-2, there is no evidence to suggest that warmer conditions in northern hemisphere summer months will reduce the effectiveness of SARS-CoV-2 transmission to an extent that few additional interventions are needed to curb its spread.
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In my view, the fact that it spreads to warmer and more humid places as well isn't really in contradiction to the idea that the virus is most potent and dangerous in a certain climatic zone. If I'm not mistaken, the flu happens around the equator as well but simply less so than it in the north where it does show seasonality.

It should be possible to estimate this: start with the outbreak in Wuhan, look at travel and transport data from Wuhan to elsewhere in the world and then look at the number of COVID-19 cases/per travel from Wuhan in different cities/regions. Then one should be able to estimate if regions in a certain climatic zone have statistically significant more cases than others.
 
My take on the distribution of hotspots along the green line of temperate climate is that this line indicates the zone of the globe that is most conducive to the proliferation of the human species as long as it lives close together indoors in spaces with recycled air. The species does quite well in subSaharan Africa and Neotropics but more often living in open air much of the time. Nothing to do with viruses.
 
Detect Covid-19 in as little as 5 minutes:
https://www.abbott.com/corpnewsroom...etect-covid-19-in-as-little-as-5-minutes.html


Abbott has received emergency use authorization (EUA) from the U.S. Food and Drug Administration (FDA) for the fastest available molecular point-of-care test for the detection of novel coronavirus (COVID-19), delivering positive results in as little as five minutes and negative results in 13 minutes.

What makes this test so different is where it can be used: outside the four walls of a traditional hospital such as in the physicians' office or urgent care clinics.
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We're ramping up production to deliver 50,000 ID NOW COVID-19 tests per day, beginning next week, to the U.S. healthcare system.
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This could come in useful given one major reason for not testing more people is a shortage of reagents to perform the tests. In a different (Danish news) piece it was reported that they tested the new method against the existing one and got the same result in 97 out of 100 tests. Not perfect but better than no tests because of the reagent shortages.
SSI has developed a simple and fast method as an alternative to the chemical kit reagents that many laboratories are lacking to perform tests for COVID19. [...]

To make the method known as quickly as possible, SSI has chosen to publish and distribute the method online and by email to European laboratory colleagues to make it widely available to other laboratories, in Denmark as well as abroad.
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https://en.ssi.dk/news/news/2020/03-ssi--solves-essential-covid19-testing-deficiency-problem
 
Forbin said:
It's amazing, considering how many blood tests I've had over the years, that I have no idea what my blood type is. Looking over the blood test reports, not one of them indicates blood type.

I imagine it's a special test, which may not have much utility unless you need a transfusion. I'm sure that you get blood typed if you go into the military, and it goes on your dog tags, for obvious reasons.
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I don't think it's a routine test. I was tested prior to an operation where they thought I might need a transfusion (I didn't in the end).
 
A number of posts about vaccine development and also about lung function have been moved here from the Worldwide spread and control thread.
Adrian said:
Interesting podcast. Although I'm not very far through yet,

Lipkin says he thinks it is the most transmittable virus we have ever seen. He also commented that its not person to person transmission but person to commonly touched thing to person which is different.

He talks about in China initial isolation strategy of shutting down areas reducing the R0 to 1.3 to 1.4 but it was when they started segregating within families they brought R0 to under 1.
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Says here that "no RNA vaccine has ever been licensed" [https://www.chemistryworld.com/news/rna-vaccines-are-coronavirus-frontrunners/4011326.article].

I think Ian Lipkin mentions the development of an "RNA vaccine" in his talk @Jonathan Edwards @Snow Leopard any views on how feasible this is?
 
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FMMM1 said:
I think Ian Lipkin mentions the development of an "RNA vaccine" in his talk @Jonathan Edwards @Snow Leopard any views on how feasible this is?
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I don't know the practical details of this as it is not my area. What I get from my nephew Al Edwards, who IS in this area, is that nobody has a proven method to take off the shelf. I would personally be surprised if a vaccine containing RNA was good - RNA is unstable. What I have heard is the suggestion of using a benign viral vector to infect human cells that carries the DNA that matches the SARS-2 RNA for something like spike protein. This would be a DNA vaccine but would work by switching on the same protein manufacture as the virus does.

A lot of the problem seems to be getting a method that infects 'spare' cells like muscle cells and gets them to produce the right amount of antigen - not too much , not too little. Muscle cells have been infected with DNA using viral vectors but nobody seems to know how easy it will be to do that with virus proteins.
 
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