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Discussion thread VI - COVID-19 (new coronavirus)
- Thread starter kiwibird
- Start date
Pathfinder
Editor, Senior Moderator
Aerosols can travel up to 10 metres, says Centre?s new Covid-19 advisory
The advisory also recommended the use of gable fan systems and roof ventilators in offices, auditoriums, shopping malls and other closed public spaces.
By: Express Web Desk | New Delhi |
Updated: May 20, 2021 7:18:00 pm
Cautioning people to maintain social distancing to prevent the transmission of the Covid-19 virus, the office of the Principal Scientific Adviser to the Government of India on Thursday said that aerosols, one of the key transmission mode of the SARS-CoV-2, can travel in the air up to 10 meters.
While sharing a set of guidelines called ?Stop the Transmission, Crush the Pandemic?, the panel said, ?Always Remember: People who show no symptoms can also spread the virus.? While stating that proper ventilation can prevent the spread of the virus, the panel added, ?Running air conditioners while keeping windows and doors shut, traps infected air inside the room, and increases risk of transmission from an infected carrier to others.?
...
https://indianexpress.com/article/i...s-says-centres-new-covid-19-advisory-7322819/
-------------------------------------------------------------------
See also:
India - Stop the Transmission, Crush the Pandemic
https://flutrackers.com/forum/forum...c-adviser-to-the-government-of-india-may-2021
The advisory also recommended the use of gable fan systems and roof ventilators in offices, auditoriums, shopping malls and other closed public spaces.
By: Express Web Desk | New Delhi |
Updated: May 20, 2021 7:18:00 pm
Cautioning people to maintain social distancing to prevent the transmission of the Covid-19 virus, the office of the Principal Scientific Adviser to the Government of India on Thursday said that aerosols, one of the key transmission mode of the SARS-CoV-2, can travel in the air up to 10 meters.
While sharing a set of guidelines called ?Stop the Transmission, Crush the Pandemic?, the panel said, ?Always Remember: People who show no symptoms can also spread the virus.? While stating that proper ventilation can prevent the spread of the virus, the panel added, ?Running air conditioners while keeping windows and doors shut, traps infected air inside the room, and increases risk of transmission from an infected carrier to others.?
...
https://indianexpress.com/article/i...s-says-centres-new-covid-19-advisory-7322819/
-------------------------------------------------------------------
See also:
India - Stop the Transmission, Crush the Pandemic
https://flutrackers.com/forum/forum...c-adviser-to-the-government-of-india-may-2021
bertrand789
New member
les avions vont continuer ? arroser les pays en vidant leurs fosses d'aisance dans le ciel ?
bertrand789
New member
6 feet or 10 metres: What experts say about safe distance to keep Covid at bay
https://www.hindustantimes.com/author/hindustantimes-com-101607439170281
https://www.hindustantimes.com/author/hindustantimes-com-101607439170281
bertrand789
New member
Dans cette crise, il y a eu bien de faux ou mauvais chiffres. Une chose est sere comme dans chaque crise certains se gavent, voir les nouveaux milliardaires des vaccins. J'ai aim? ceci :
Coronavirus : "La Chine est quasiment d'barrasse" du virus, dit Arnauld Miguet
https://www.rtl.fr/actu/internationa...uet-7900034022
Tout est dans le quasiment. Je ne suis pas un pro des humains, donc aussi longtemps que vous laisserez les animaux tranquille , amusez vous. Mais franchement, si pour les animaux on use et ou abuse de la rigueur, mais avec des r?sultats: des vrais r?sultats, il va falloir pr?voir de sacr?s financements pour les animaux.
Il va falloir de sacr?s financements car ce sont les humains qui rendent les animaux malade. Prenons comme exemple les ?levages de visons , c'est quoi le financement pour la destruction des outils de travail ? Pour imaginer ce que devrait et ou pourrait ?tre un financement plus objectif : il faudrait donner quoi pour ?liminer les chats de compagnie porteur de covid et donc potentiellement cr?ateur de variant ?
Si l'O.M.S et la F.AO. sont ? r?former, pardon repenser, totalement, les C.D.C , franchement, cela m?rite une s?rieuse, pardon tr?s s?rieuse, mise ? niveau ... Pour faire entrevoir, les diff?rences de monde: les animaux de production sont des animaux qui ne connaissent pas la maladie au cours de leur vie. C'est normal car on ne doit plus conduire un animal malade ? l'abattoir . Le normal , pour l'humain semble de mourir malade . Faire cohabiter ces deux mondes en un m?me lieu, ce que pr?voie ONE HEALTH va demander de tr?s s?rieuses remises ? niveau.
Les animaux de compagnie , eux meurent malade aussi, il va peut ?tre un jour regarder pourquoi ? Je pense en particulier ? tous ces humains , atteint du syndrome de Noe, qui produisent avec beaucoup d'?nergie des lieux de maladie ...
https://de.wikipedia.org/wiki/Tierhortung
le magasin allemand record :
https://www.arte.tv/fr/videos/100300...-de-compagnie/
c'est une bombe . Demander aux scientifiques de faire un peu moins bien , avec l'argent des autres, c'est normal , mais ce sont les soci?t?s qui doivent changer leur rapport avec le vivant ...
plus de 3000 esp?ces propos?es ? la vente ... Je connais un peu ce milieu, car dans une autre vie , je les ai aid?, pour entrevoir leurs fonctionnements . Entrevoir les portages potentiels des animaux ? sang froid , consid?r?s , comme sain, cela permet de grandir un peu ...
Pour le fun , un tel lieu qui re?oit des humains porteurs de bien des choses, c'est pas pire que les march?s humides de Wuhan qui ont ?t? trait?s avec un m?pris, juste indigne ...
Coronavirus : "La Chine est quasiment d'barrasse" du virus, dit Arnauld Miguet
https://www.rtl.fr/actu/internationa...uet-7900034022
Tout est dans le quasiment. Je ne suis pas un pro des humains, donc aussi longtemps que vous laisserez les animaux tranquille , amusez vous. Mais franchement, si pour les animaux on use et ou abuse de la rigueur, mais avec des r?sultats: des vrais r?sultats, il va falloir pr?voir de sacr?s financements pour les animaux.
Il va falloir de sacr?s financements car ce sont les humains qui rendent les animaux malade. Prenons comme exemple les ?levages de visons , c'est quoi le financement pour la destruction des outils de travail ? Pour imaginer ce que devrait et ou pourrait ?tre un financement plus objectif : il faudrait donner quoi pour ?liminer les chats de compagnie porteur de covid et donc potentiellement cr?ateur de variant ?
Si l'O.M.S et la F.AO. sont ? r?former, pardon repenser, totalement, les C.D.C , franchement, cela m?rite une s?rieuse, pardon tr?s s?rieuse, mise ? niveau ... Pour faire entrevoir, les diff?rences de monde: les animaux de production sont des animaux qui ne connaissent pas la maladie au cours de leur vie. C'est normal car on ne doit plus conduire un animal malade ? l'abattoir . Le normal , pour l'humain semble de mourir malade . Faire cohabiter ces deux mondes en un m?me lieu, ce que pr?voie ONE HEALTH va demander de tr?s s?rieuses remises ? niveau.
Les animaux de compagnie , eux meurent malade aussi, il va peut ?tre un jour regarder pourquoi ? Je pense en particulier ? tous ces humains , atteint du syndrome de Noe, qui produisent avec beaucoup d'?nergie des lieux de maladie ...
https://de.wikipedia.org/wiki/Tierhortung
le magasin allemand record :
https://www.arte.tv/fr/videos/100300...-de-compagnie/
c'est une bombe . Demander aux scientifiques de faire un peu moins bien , avec l'argent des autres, c'est normal , mais ce sont les soci?t?s qui doivent changer leur rapport avec le vivant ...
plus de 3000 esp?ces propos?es ? la vente ... Je connais un peu ce milieu, car dans une autre vie , je les ai aid?, pour entrevoir leurs fonctionnements . Entrevoir les portages potentiels des animaux ? sang froid , consid?r?s , comme sain, cela permet de grandir un peu ...
Pour le fun , un tel lieu qui re?oit des humains porteurs de bien des choses, c'est pas pire que les march?s humides de Wuhan qui ont ?t? trait?s avec un m?pris, juste indigne ...
Last edited by a moderator:
Pathfinder
Editor, Senior Moderator
Immunity to the Coronavirus May Persist for Years, Scientists Find
Important immune cells survive in the bone marrow of people who were infected with the virus or were inoculated against it, new research suggests.
By Apoorva Mandavilli
May 26, 2021Updated 4:12 p.m. ET
Immunity to the coronavirus lasts at least a year, possibly a lifetime, improving over time especially after vaccination, according to two new studies. The findings may help put to rest lingering fears that protection against the virus will be short-lived.
Together, the studies suggest that most people who have recovered from Covid-19 and who were later immunized will not need boosters. Vaccinated people who were never infected most likely will need the shots, however, as will a minority who were infected but did not produce a robust immune response.
Both reports looked at people who had been exposed to the coronavirus about a year earlier. Cells that retain a memory of the virus persist in the bone marrow and may churn out antibodies whenever needed, according to one of the studies, published on Monday in the journal Nature.
The other study, posted online at BioRxiv, a site for biology research, found that these so-called memory B cells continue to mature and strengthen for at least 12 months after the initial infection.
...
https://www.nytimes.com/2021/05/26/health/coronavirus-immunity-vaccines.html
Important immune cells survive in the bone marrow of people who were infected with the virus or were inoculated against it, new research suggests.
By Apoorva Mandavilli
May 26, 2021Updated 4:12 p.m. ET
Immunity to the coronavirus lasts at least a year, possibly a lifetime, improving over time especially after vaccination, according to two new studies. The findings may help put to rest lingering fears that protection against the virus will be short-lived.
Together, the studies suggest that most people who have recovered from Covid-19 and who were later immunized will not need boosters. Vaccinated people who were never infected most likely will need the shots, however, as will a minority who were infected but did not produce a robust immune response.
Both reports looked at people who had been exposed to the coronavirus about a year earlier. Cells that retain a memory of the virus persist in the bone marrow and may churn out antibodies whenever needed, according to one of the studies, published on Monday in the journal Nature.
The other study, posted online at BioRxiv, a site for biology research, found that these so-called memory B cells continue to mature and strengthen for at least 12 months after the initial infection.
...
https://www.nytimes.com/2021/05/26/health/coronavirus-immunity-vaccines.html
sharon sanders
Editor-in-Chief & President
Nature . SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans
https://flutrackers.com/forum/forum...discussion-thread-vi-covid-19-new-coronavirus
https://flutrackers.com/forum/forum...discussion-thread-vi-covid-19-new-coronavirus
Last edited:
sharon sanders
Editor-in-Chief & President
Just a reminder.....
We have long standing policies against any bashing. I know we lost a lot of participants at the beginning of the pandemic when we would not allow any bashing against that current US president on pandemic issues.
Nothing has changed.
We are not allowing any derogatory personal attacks against any US admin official, W.H.O. personnel, any officials in any country, researchers, any persons at all. These are real people. They have families, careers...Please notice in the thread about the possibility of a lab leak origin in China, I never directed my comments to any Chinese person, official, researcher.
We are not able to make any real determinations of what has happened. As the damage of the pandemic is assessed, those in positions to have affected policies will be scrutinized. And there will be some scapegoating. We need to rely on the tribunals that will follow to see the evidence that will be presented and argued. I have been advocating for a world court under established international law for a year.
There will be accountability.
So in the interest of dignity there is no bashing. There are many sites that allow unfettered bashing. In fact, most of main stream media (who previously were news organizations) engage in character assassination. We are not doing it here.
We can state our disagreements on actions and policies, but the personal attacks are out.
Thank you for participating. I know we are boring, but that is us.
We have long standing policies against any bashing. I know we lost a lot of participants at the beginning of the pandemic when we would not allow any bashing against that current US president on pandemic issues.
Nothing has changed.
We are not allowing any derogatory personal attacks against any US admin official, W.H.O. personnel, any officials in any country, researchers, any persons at all. These are real people. They have families, careers...Please notice in the thread about the possibility of a lab leak origin in China, I never directed my comments to any Chinese person, official, researcher.
We are not able to make any real determinations of what has happened. As the damage of the pandemic is assessed, those in positions to have affected policies will be scrutinized. And there will be some scapegoating. We need to rely on the tribunals that will follow to see the evidence that will be presented and argued. I have been advocating for a world court under established international law for a year.
There will be accountability.
So in the interest of dignity there is no bashing. There are many sites that allow unfettered bashing. In fact, most of main stream media (who previously were news organizations) engage in character assassination. We are not doing it here.
We can state our disagreements on actions and policies, but the personal attacks are out.
Thank you for participating. I know we are boring, but that is us.
Today 8 Q498K sequences from Slovenia were disclosed in the GISAID database. 498K is as i understand expected to have a similar effect to Q498R. This latter substitution together with N501Y and another b.1.1.7 mutation was shown to have a 600x increased affinity. Let's keep an eye on Slovenia :surrender:
Does anyone know more about this ?
Does anyone know more about this ?
Pathfinder
Editor, Senior Moderator
Translation Google
Covid, Italian study: this is how the sun destroys the virus in seconds
01 June 2021 | 15.39
READING: 3 minutes
Clerici all'Adnkronos: "On the beach after 10-20 seconds he's done for"
"We have shown that UVA and UVB rays from the sun completely kill Sars-Cov-2 within a few tens of seconds". This was stated by Mario Clerici, professor of General Pathology at the State University of Milan and scientific director of the Irccs of Milan Don Gnocchi Foundation, author, together with the research group of the National Institute of Astrophysics, of an all-Italian study published today in preprint .
immunologist - the time needed, for example when you are on the beach with the sun being amplified by the glare on the sand or on the water, is even shorter. So on the beach - says Clerici - 10-20 seconds of Uva and Uvb are really enough to completely kill the virus ".
"Our idea - explains the researcher - is that this, together with the ever higher percentage of vaccinated people, explains why with the warm season we are overcoming the problem". So why did an avalanche of infections occur in Brazil during the summer, as well as in India? "First of all, it must be said that the sun - underlines Clerici - is not the only element that justifies everything we observe. In India, religious festivals contributed with bathing in the Ganges and then there were monsoons, so there is it was all the haze of the sun's rays due to the clouds. In Brazil we all know what happened - adds the immunologist - unfortunately they paid for the Bolsonaro management, because it is true that the sun's rays are needed but also masks, vaccines and everything the rest".
In any case, the experiments confirmed the effectiveness of the sun against Covid-19. "You can see in a visualization - says the immunologist - the effect of the sun's rays on the virus: if you don't expose it to the sun's rays the virus infects the cells, if you expose it to the sun you kill it".
A discovery that could have excellent applications in everyday life to sterilize objects and environments from the virus. "Last year's data were important because they led to the development of devices that performed precisely this function but Uvc rays - recalls the scientist - are dangerous for the human skin, so you could not stay in the same room where they were applied. Uvb rays instead no, they are the rays that normally touch us when we go out in the sun, so this discovery has a much higher importance ". In short, if we put normal solar lamps in the buses could we solve a problem? "Yes. Apart from the fact that we will all come out more tanned and more beautiful, what these data suggest is just that."
But let's see how the experimental demonstration of this discovery came about. "The astrophysicists connected a machine that produces the different solar rays in a distinct way, so only grapes or UVBs or UVCs rather than ultraviolet - explains Clerici - then we put the machine under a hood, we took the lung cells and we threw on the virus. And the virus that has been exposed or not to the different components of the sun's rays. At first - explains the immunologist - we used a maximum dose of virus, therefore much much higher than that which occurs in a subject with Covid. And then we used the dose present in a patient with severe Covid, to see if it could also have potential clinical importance. And indeed it is like this:
https://www.adnkronos.com/covid-stu...virus-in-pochi-secondi_35FqxEpnoSElrlB3thFfR1
Covid, Italian study: this is how the sun destroys the virus in seconds
01 June 2021 | 15.39
READING: 3 minutes
Clerici all'Adnkronos: "On the beach after 10-20 seconds he's done for"
"We have shown that UVA and UVB rays from the sun completely kill Sars-Cov-2 within a few tens of seconds". This was stated by Mario Clerici, professor of General Pathology at the State University of Milan and scientific director of the Irccs of Milan Don Gnocchi Foundation, author, together with the research group of the National Institute of Astrophysics, of an all-Italian study published today in preprint .
immunologist - the time needed, for example when you are on the beach with the sun being amplified by the glare on the sand or on the water, is even shorter. So on the beach - says Clerici - 10-20 seconds of Uva and Uvb are really enough to completely kill the virus ".
"Our idea - explains the researcher - is that this, together with the ever higher percentage of vaccinated people, explains why with the warm season we are overcoming the problem". So why did an avalanche of infections occur in Brazil during the summer, as well as in India? "First of all, it must be said that the sun - underlines Clerici - is not the only element that justifies everything we observe. In India, religious festivals contributed with bathing in the Ganges and then there were monsoons, so there is it was all the haze of the sun's rays due to the clouds. In Brazil we all know what happened - adds the immunologist - unfortunately they paid for the Bolsonaro management, because it is true that the sun's rays are needed but also masks, vaccines and everything the rest".
In any case, the experiments confirmed the effectiveness of the sun against Covid-19. "You can see in a visualization - says the immunologist - the effect of the sun's rays on the virus: if you don't expose it to the sun's rays the virus infects the cells, if you expose it to the sun you kill it".
A discovery that could have excellent applications in everyday life to sterilize objects and environments from the virus. "Last year's data were important because they led to the development of devices that performed precisely this function but Uvc rays - recalls the scientist - are dangerous for the human skin, so you could not stay in the same room where they were applied. Uvb rays instead no, they are the rays that normally touch us when we go out in the sun, so this discovery has a much higher importance ". In short, if we put normal solar lamps in the buses could we solve a problem? "Yes. Apart from the fact that we will all come out more tanned and more beautiful, what these data suggest is just that."
But let's see how the experimental demonstration of this discovery came about. "The astrophysicists connected a machine that produces the different solar rays in a distinct way, so only grapes or UVBs or UVCs rather than ultraviolet - explains Clerici - then we put the machine under a hood, we took the lung cells and we threw on the virus. And the virus that has been exposed or not to the different components of the sun's rays. At first - explains the immunologist - we used a maximum dose of virus, therefore much much higher than that which occurs in a subject with Covid. And then we used the dose present in a patient with severe Covid, to see if it could also have potential clinical importance. And indeed it is like this:
https://www.adnkronos.com/covid-stu...virus-in-pochi-secondi_35FqxEpnoSElrlB3thFfR1
sharon sanders
Editor-in-Chief & President
Wang Guiqiang, member of the expert team of the National Health Commission and director of the Department of Infectious Diseases of Peking University First Hospital:
snip
After the outbreak of the Guangdong epidemic, the R0 index has been increasing since May 25 and reached its peak on the 29th. 6.06. Starting on May 30, the value of R0 has dropped to 4.19.
“It is conceivable that the difficulty of epidemic prevention that Guangzhou is facing this time is unprecedented. Conventional tactics can no longer meet the new epidemic prevention needs.
https://flutrackers.com/forum/forum/...619#post916619
snip
After the outbreak of the Guangdong epidemic, the R0 index has been increasing since May 25 and reached its peak on the 29th. 6.06. Starting on May 30, the value of R0 has dropped to 4.19.
“It is conceivable that the difficulty of epidemic prevention that Guangzhou is facing this time is unprecedented. Conventional tactics can no longer meet the new epidemic prevention needs.
https://flutrackers.com/forum/forum/...619#post916619
Emily
Editor, Senior Moderator
https://www.biorxiv.org/content/10.1101/2021.05.28.446163v1.abstract
The SARS-CoV-2 variants associated with infections in India, B.1.617, show enhanced spike cleavage by furin
https://www.nature.com/articles/s41564-021-00908-w
The furin cleavage site in the SARS-CoV-2 spike protein is required for transmission in ferrets
We also note that the SARS-CoV-2 CS remains suboptimal for furin cleavage. It is unclear if this is a trade-off (that is, with stability of spike) or whether further optimization of this site could result in higher transmissibility. In this regard, multiple SARS-CoV-2 variants have recently emerged and spread rapidly, including some, such as the B.1.1.7 ‘UK’ variant, that have mutations proximal to the S1/S2 CS predicted to enhance furin cleavage. This further emphasizes the role of this site for virus transmission and the importance of continued monitoring as SARS-CoV-2 circulates in the human population
The SARS-CoV-2 variants associated with infections in India, B.1.617, show enhanced spike cleavage by furin
https://www.nature.com/articles/s41564-021-00908-w
The furin cleavage site in the SARS-CoV-2 spike protein is required for transmission in ferrets
We also note that the SARS-CoV-2 CS remains suboptimal for furin cleavage. It is unclear if this is a trade-off (that is, with stability of spike) or whether further optimization of this site could result in higher transmissibility. In this regard, multiple SARS-CoV-2 variants have recently emerged and spread rapidly, including some, such as the B.1.1.7 ‘UK’ variant, that have mutations proximal to the S1/S2 CS predicted to enhance furin cleavage. This further emphasizes the role of this site for virus transmission and the importance of continued monitoring as SARS-CoV-2 circulates in the human population
Pathfinder
Editor, Senior Moderator
Necessity of COVID-19 vaccination in previously infected individuals
View ORCID ProfileNabin K. Shrestha, Patrick C. Burke, Amy S. Nowacki, Paul Terpeluk, Steven M. Gordon
doi: https://doi.org/10.1101/2021.06.01.21258176
This article is a preprint and has not been certified by peer review [what does this mean?]. It reports new medical research that has yet to be evaluated and so should not be used to guide clinical practice.
ABSTRACT
Background The purpose of this study was to evaluate the necessity of COVID-19 vaccination in persons previously infected with SARS-CoV-2.
Methods Employees of the Cleveland Clinic Health System working in Ohio on Dec 16, 2020, the day COVID-19 vaccination was started, were included. Any subject who tested positive for SARS-CoV-2 at least 42 days earlier was considered previously infected. One was considered vaccinated 14 days after receipt of the second dose of a SARS-CoV-2 mRNA vaccine. The cumulative incidence of SARS-CoV-2 infection over the next five months, among previously infected subjects who received the vaccine, was compared with those of previously infected subjects who remained unvaccinated, previously uninfected subjects who received the vaccine, and previously uninfected subjects who remained unvaccinated.
Results Among the 52238 included employees, 1359 (53%) of 2579 previously infected subjects remained unvaccinated, compared with 22777 (41%) of 49659 not previously infected. The cumulative incidence of SARS-CoV-2 infection remained almost zero among previously infected unvaccinated subjects, previously infected subjects who were vaccinated, and previously uninfected subjects who were vaccinated, compared with a steady increase in cumulative incidence among previously uninfected subjects who remained unvaccinated. Not one of the 1359 previously infected subjects who remained unvaccinated had a SARS-CoV-2 infection over the duration of the study. In a Cox proportional hazards regression model, after adjusting for the phase of the epidemic, vaccination was associated with a significantly lower risk of SARS-CoV-2 infection among those not previously infected (HR 0.031, 95% CI 0.015 to 0.061) but not among those previously infected (HR 0.313, 95% CI 0 to Infinity).
Conclusions Individuals who have had SARS-CoV-2 infection are unlikely to benefit from COVID-19 vaccination, and vaccines can be safely prioritized to those who have not been infected before.
...
https://www.medrxiv.org/content/10.1....01.21258176v2
View ORCID ProfileNabin K. Shrestha, Patrick C. Burke, Amy S. Nowacki, Paul Terpeluk, Steven M. Gordon
doi: https://doi.org/10.1101/2021.06.01.21258176
This article is a preprint and has not been certified by peer review [what does this mean?]. It reports new medical research that has yet to be evaluated and so should not be used to guide clinical practice.
ABSTRACT
Background The purpose of this study was to evaluate the necessity of COVID-19 vaccination in persons previously infected with SARS-CoV-2.
Methods Employees of the Cleveland Clinic Health System working in Ohio on Dec 16, 2020, the day COVID-19 vaccination was started, were included. Any subject who tested positive for SARS-CoV-2 at least 42 days earlier was considered previously infected. One was considered vaccinated 14 days after receipt of the second dose of a SARS-CoV-2 mRNA vaccine. The cumulative incidence of SARS-CoV-2 infection over the next five months, among previously infected subjects who received the vaccine, was compared with those of previously infected subjects who remained unvaccinated, previously uninfected subjects who received the vaccine, and previously uninfected subjects who remained unvaccinated.
Results Among the 52238 included employees, 1359 (53%) of 2579 previously infected subjects remained unvaccinated, compared with 22777 (41%) of 49659 not previously infected. The cumulative incidence of SARS-CoV-2 infection remained almost zero among previously infected unvaccinated subjects, previously infected subjects who were vaccinated, and previously uninfected subjects who were vaccinated, compared with a steady increase in cumulative incidence among previously uninfected subjects who remained unvaccinated. Not one of the 1359 previously infected subjects who remained unvaccinated had a SARS-CoV-2 infection over the duration of the study. In a Cox proportional hazards regression model, after adjusting for the phase of the epidemic, vaccination was associated with a significantly lower risk of SARS-CoV-2 infection among those not previously infected (HR 0.031, 95% CI 0.015 to 0.061) but not among those previously infected (HR 0.313, 95% CI 0 to Infinity).
Conclusions Individuals who have had SARS-CoV-2 infection are unlikely to benefit from COVID-19 vaccination, and vaccines can be safely prioritized to those who have not been infected before.
...
https://www.medrxiv.org/content/10.1....01.21258176v2