Jeff Gilchrist
@jeffgilchrist.bsky.social
PhD Biomedical researcher, data scientist, and finder of large prime numbers. Views are my own. Twitter: @jeffgilchrist Mastadon: @[email protected]
COVID-19 guides, stats, calculators & 600+ scientific articles: http://covid.gilchrist.ca
COVID-19 guides, stats, calculators & 600+ scientific articles: http://covid.gilchrist.ca
Pinned
Jeff Gilchrist
@jeffgilchrist.bsky.social
· Nov 10
COVID-19: Stats, Guides, Articles, Calculators
COVID-19 guides, useful info, stats, calculators & 600+ scientific articles: covid.gilchrist.ca
Ottawa, Canada weekly stats: covid.gilchrist.ca/Ottawa.html
Ontario, Canada weekly stats: covid.gilchrist.ca/Ontario.html
🧪🧵 1/
COVID-19 guides, useful info, stats, calculators & 600+ scientific articles: covid.gilchrist.ca
Ottawa, Canada weekly stats: covid.gilchrist.ca/Ottawa.html
Ontario, Canada weekly stats: covid.gilchrist.ca/Ontario.html
🧪🧵 1/
Thread @virusesimmunity.bsky.social "A ground breaking paper by Shady Younis et al. @stanfordimmunology.bsky.social provides an answer to the long-standing question about how EBV infections are linked to lupus. A short thread to explain the key findings." ( threadreaderapp.com/thread/19891... )
Thread by @VirusesImmunity on Thread Reader App
@VirusesImmunity: A groundbreaking paper by @younis_sh1 et al. @stanfordimmuno provides an answer to the long-standing question about how EBV infections are linked to lupus. A short thread to explain ...
threadreaderapp.com
November 14, 2025 at 1:05 PM
Thread @virusesimmunity.bsky.social "A ground breaking paper by Shady Younis et al. @stanfordimmunology.bsky.social provides an answer to the long-standing question about how EBV infections are linked to lupus. A short thread to explain the key findings." ( threadreaderapp.com/thread/19891... )
Reposted by Jeff Gilchrist
After some finagling to get the assembly procedure just right we are finally releasing the aluminum bodied POLARIS air purifier, made-in-Canada and based on the open-source design by Zack Deis.
1/3
#airpurifier #indoorairquality #covidisairborne
1/3
#airpurifier #indoorairquality #covidisairborne
November 11, 2025 at 12:05 AM
After some finagling to get the assembly procedure just right we are finally releasing the aluminum bodied POLARIS air purifier, made-in-Canada and based on the open-source design by Zack Deis.
1/3
#airpurifier #indoorairquality #covidisairborne
1/3
#airpurifier #indoorairquality #covidisairborne
Reposted by Jeff Gilchrist
How does various mask fit compare to filter the air and protect you or others?
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
October 25, 2025 at 11:09 AM
How does various mask fit compare to filter the air and protect you or others?
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
Reposted by Jeff Gilchrist
What was life really like before vaccines? The story of what happened to 8-year old George Williams in August 1852 gives us a glimpse.
open.substack.com/pub/epiellie...
open.substack.com/pub/epiellie...
Here's what life before vaccines was really like
The morning of August 2nd 1852 promised a lovely summer’s day in London. But not for 8 year old George Williams.
open.substack.com
October 26, 2025 at 2:11 PM
What was life really like before vaccines? The story of what happened to 8-year old George Williams in August 1852 gives us a glimpse.
open.substack.com/pub/epiellie...
open.substack.com/pub/epiellie...
How does various mask fit compare to filter the air and protect you or others?
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
October 25, 2025 at 11:09 AM
How does various mask fit compare to filter the air and protect you or others?
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
Most masks, even baggy blue procedure masks use filtering material that can filter 95%+ of particles that pass through it, but the key is "pass through it". Continue to learn more... 🧪🧵1/
** Ontario Variant Update (to Oct. 3, 2025) **
The XFG.* "Stratus" family is accounting for 83% while the next closest variant family NB.1.8.1.* "Nimbus" is 12.8% of sequenced genomes from COVID tests. 🧵1/
The XFG.* "Stratus" family is accounting for 83% while the next closest variant family NB.1.8.1.* "Nimbus" is 12.8% of sequenced genomes from COVID tests. 🧵1/
October 19, 2025 at 12:18 PM
** Ontario Variant Update (to Oct. 3, 2025) **
The XFG.* "Stratus" family is accounting for 83% while the next closest variant family NB.1.8.1.* "Nimbus" is 12.8% of sequenced genomes from COVID tests. 🧵1/
The XFG.* "Stratus" family is accounting for 83% while the next closest variant family NB.1.8.1.* "Nimbus" is 12.8% of sequenced genomes from COVID tests. 🧵1/
Health Canada has published Guidance for Indoor Air Quality Professionals, a practical, science-based resource for Indoor Air Quality (IAQ) experts, building operators, and employers.
Article ( ospe.on.ca/advocacy/pol... )
Guidelines ( www.canada.ca/en/health-ca... )
Article ( ospe.on.ca/advocacy/pol... )
Guidelines ( www.canada.ca/en/health-ca... )
Policy Win: Health Canada Releases New IAQ Guidance
Health Canada announces new IAQ guidance, providing essential insights for improving indoor air quality and safety in buildings.
ospe.on.ca
October 15, 2025 at 8:14 PM
Health Canada has published Guidance for Indoor Air Quality Professionals, a practical, science-based resource for Indoor Air Quality (IAQ) experts, building operators, and employers.
Article ( ospe.on.ca/advocacy/pol... )
Guidelines ( www.canada.ca/en/health-ca... )
Article ( ospe.on.ca/advocacy/pol... )
Guidelines ( www.canada.ca/en/health-ca... )
Reposted by Jeff Gilchrist
In new study led by @bdadonaite.bsky.social, we measure how spike mutations affect function & antigenicity of spike of KP.3.1.1 strain of SARS-CoV-2.
Sheds light on how key neutralizing epitopes are changing & importance of RBD up/down motion.
www.biorxiv.org/content/10.1...
Sheds light on how key neutralizing epitopes are changing & importance of RBD up/down motion.
www.biorxiv.org/content/10.1...
Spike mutations that affect the function and antigenicity of recent KP.3.1.1-like SARS-CoV-2 variants
SARS-CoV-2 is under strong evolutionary selection to acquire mutations in its spike protein that reduce neutralization by human polyclonal antibodies. Here we use pseudovirus-based deep mutational sca...
www.biorxiv.org
August 20, 2025 at 5:22 AM
In new study led by @bdadonaite.bsky.social, we measure how spike mutations affect function & antigenicity of spike of KP.3.1.1 strain of SARS-CoV-2.
Sheds light on how key neutralizing epitopes are changing & importance of RBD up/down motion.
www.biorxiv.org/content/10.1...
Sheds light on how key neutralizing epitopes are changing & importance of RBD up/down motion.
www.biorxiv.org/content/10.1...
Reposted by Jeff Gilchrist
The final published version of this study is now available in Journal of Virology at journals.asm.org/doi/10.1128/...
Spike mutations that affect the function and antigenicity of recent KP.3.1.1-like SARS-CoV-2 variants | Journal of Virology
This study measures how mutations to the spike of a SARS-CoV-2 variant that circulated
in early 2025 affect its function and recognition by both the polyclonal antibodies
produced by the human immune ...
journals.asm.org
October 14, 2025 at 4:22 PM
The final published version of this study is now available in Journal of Virology at journals.asm.org/doi/10.1128/...
Reposted by Jeff Gilchrist
In new study led by @ckikawa.bsky.social, we provide near real-time data on human neutralizing antibody landscape to influenza by measuring ~26,000 titers to >100 recent viral strains
Data can inform vaccine selection & evolutionary/epidemiological modeling
www.biorxiv.org/content/10.1...
Data can inform vaccine selection & evolutionary/epidemiological modeling
www.biorxiv.org/content/10.1...
Near real-time data on the human neutralizing antibody landscape to influenza virus to inform vaccine-strain selection in September 2025
The hemagglutinin of human influenza virus evolves rapidly to erode neutralizing antibody immunity. Twice per year, new vaccine strains are selected with the goal of providing maximum protection again...
www.biorxiv.org
September 8, 2025 at 9:48 PM
In new study led by @ckikawa.bsky.social, we provide near real-time data on human neutralizing antibody landscape to influenza by measuring ~26,000 titers to >100 recent viral strains
Data can inform vaccine selection & evolutionary/epidemiological modeling
www.biorxiv.org/content/10.1...
Data can inform vaccine selection & evolutionary/epidemiological modeling
www.biorxiv.org/content/10.1...
Reposted by Jeff Gilchrist
Such an important piece. The positive momentum behind clean indoor air is palpable. But we’re not there yet as my last post demonstrates. Please read and share and get behind this cause.
theconversation.com/why-investme...
theconversation.com/why-investme...
Why investment in clean indoor air is vital preparation for the pandemics and climate emergencies to come
Unchecked airborne infections cost billions in lost health and productivity each year – likely more than the cost of better ventilation to clean up indoor air.
theconversation.com
October 1, 2025 at 11:12 PM
Such an important piece. The positive momentum behind clean indoor air is palpable. But we’re not there yet as my last post demonstrates. Please read and share and get behind this cause.
theconversation.com/why-investme...
theconversation.com/why-investme...
I found out for Ontario that "the Ministry of Health updated the age groups on the I9 bed census data collection forms" so some data in the Ontario Respiratory Virus Tool ( www.publichealthontario.ca/en/Data-and-... ) will be grouped differently starting in September. 🧵1/
September 29, 2025 at 12:22 PM
I found out for Ontario that "the Ministry of Health updated the age groups on the I9 bed census data collection forms" so some data in the Ontario Respiratory Virus Tool ( www.publichealthontario.ca/en/Data-and-... ) will be grouped differently starting in September. 🧵1/
Reposted by Jeff Gilchrist
🧪 Can researchers stop AI from fabricating citations? Probably not entirely.
While models like GPT-5 are improving, hallucination is fundamental to their statistical design, shifting the burden onto users to build new intuitions for an AI age.
#MLSky #AcademicSky
While models like GPT-5 are improving, hallucination is fundamental to their statistical design, shifting the burden onto users to build new intuitions for an AI age.
#MLSky #AcademicSky
Can researchers stop AI making up citations?
OpenAI’s GPT-5 hallucinates less than previous models do, but cutting hallucination completely might prove impossible.
www.nature.com
September 9, 2025 at 3:27 PM
🧪 Can researchers stop AI from fabricating citations? Probably not entirely.
While models like GPT-5 are improving, hallucination is fundamental to their statistical design, shifting the burden onto users to build new intuitions for an AI age.
#MLSky #AcademicSky
While models like GPT-5 are improving, hallucination is fundamental to their statistical design, shifting the burden onto users to build new intuitions for an AI age.
#MLSky #AcademicSky
*** Ontario Variant Update (to: Aug. 16, 2025) ***
Ontario COVID sequence updates have been more frequent over the past month with the XFG.* "Stratus" family of variants now at 74% of sequences, NB.1.8.1.* "Nimbus" at 22% and LP.8.1.* down to 3%. #Variants #COVID #XFG #Stratus 🧪🧵1/
Ontario COVID sequence updates have been more frequent over the past month with the XFG.* "Stratus" family of variants now at 74% of sequences, NB.1.8.1.* "Nimbus" at 22% and LP.8.1.* down to 3%. #Variants #COVID #XFG #Stratus 🧪🧵1/
September 9, 2025 at 12:08 PM
Reposted by Jeff Gilchrist
A fascinating new preprint w/one very unexpected finding suggests, I believe, that a large proportion of Long Covid may be due to chronic infection in a particular bodily niche, which could be crucial for finding effective LC treatments. It requires some explaining. 🧵 1/33
September 2, 2025 at 3:16 AM
A fascinating new preprint w/one very unexpected finding suggests, I believe, that a large proportion of Long Covid may be due to chronic infection in a particular bodily niche, which could be crucial for finding effective LC treatments. It requires some explaining. 🧵 1/33
Reposted by Jeff Gilchrist
For the next little while, all donations will be matched by a generous corporate sponsor.
That means your donation will go twice as far–so donate today!
#DoubleYourImpact #YallMasking
That means your donation will go twice as far–so donate today!
#DoubleYourImpact #YallMasking
August 27, 2025 at 5:01 PM
For the next little while, all donations will be matched by a generous corporate sponsor.
That means your donation will go twice as far–so donate today!
#DoubleYourImpact #YallMasking
That means your donation will go twice as far–so donate today!
#DoubleYourImpact #YallMasking
Reposted by Jeff Gilchrist
This links to a press release - we need some media coverage, yo! Please send the press release out to Canadian journos. 💕 thank you! #cdnpoli #nbpoli #ableg #nspoli #peipoli
#Z94.4
The Canadian Aerosol Transmission Coalition put out a statement supporting CSA’s revisions to Z94.4. Over 1,700 individuals and organizations signed on to the statement - including unions representing over 3 million workers in 🇨🇦. www.globenewswire.com/news-release...
The Canadian Aerosol Transmission Coalition put out a statement supporting CSA’s revisions to Z94.4. Over 1,700 individuals and organizations signed on to the statement - including unions representing over 3 million workers in 🇨🇦. www.globenewswire.com/news-release...
Protecting healthcare workers protects us all:
Canadian coalition gets overwhelming support backing stronger protections for healthcare workers in updated CSA respirator standard...
www.globenewswire.com
August 27, 2025 at 11:45 AM
Reposted by Jeff Gilchrist
Thank-yous from our donors mean the world to us! 💙
Donate A Mask is 100% powered by volunteers, and knowing our work is helping others stay safe and healthy is what keeps us going! 😷
Consider donating to support our work.
donatemask.ca/fundraiser
#StillMasking and #StillSaltingTheVibes
Donate A Mask is 100% powered by volunteers, and knowing our work is helping others stay safe and healthy is what keeps us going! 😷
Consider donating to support our work.
donatemask.ca/fundraiser
#StillMasking and #StillSaltingTheVibes
August 24, 2025 at 10:09 PM
Thank-yous from our donors mean the world to us! 💙
Donate A Mask is 100% powered by volunteers, and knowing our work is helping others stay safe and healthy is what keeps us going! 😷
Consider donating to support our work.
donatemask.ca/fundraiser
#StillMasking and #StillSaltingTheVibes
Donate A Mask is 100% powered by volunteers, and knowing our work is helping others stay safe and healthy is what keeps us going! 😷
Consider donating to support our work.
donatemask.ca/fundraiser
#StillMasking and #StillSaltingTheVibes
Reposted by Jeff Gilchrist
DYK our Free Request Program offers respirator #masks in 5 different styles & multiple sizes, including small masks for kids? 😷
Consider donating to support our Free Request Program. Right now, every dollar will be matched by our corporate sponsor!
donatemask.ca/fundraiser
#MaskUp #StillMasking
Consider donating to support our Free Request Program. Right now, every dollar will be matched by our corporate sponsor!
donatemask.ca/fundraiser
#MaskUp #StillMasking
August 23, 2025 at 11:13 PM
DYK our Free Request Program offers respirator #masks in 5 different styles & multiple sizes, including small masks for kids? 😷
Consider donating to support our Free Request Program. Right now, every dollar will be matched by our corporate sponsor!
donatemask.ca/fundraiser
#MaskUp #StillMasking
Consider donating to support our Free Request Program. Right now, every dollar will be matched by our corporate sponsor!
donatemask.ca/fundraiser
#MaskUp #StillMasking
Reposted by Jeff Gilchrist
If #masks and clean air tools are on your back-to-school shopping list, consider stocking up at our charity fundraising store. 🛍️
🛒 donatemask.ca/shop
Our kid-sized masks are on sale at super low prices! 😷
#CleanAirForAll #MaskUp
🛒 donatemask.ca/shop
Our kid-sized masks are on sale at super low prices! 😷
#CleanAirForAll #MaskUp
August 18, 2025 at 1:56 AM
If #masks and clean air tools are on your back-to-school shopping list, consider stocking up at our charity fundraising store. 🛍️
🛒 donatemask.ca/shop
Our kid-sized masks are on sale at super low prices! 😷
#CleanAirForAll #MaskUp
🛒 donatemask.ca/shop
Our kid-sized masks are on sale at super low prices! 😷
#CleanAirForAll #MaskUp
Reposted by Jeff Gilchrist
New fundraiser alert! 📢 Woot woot!
A very generous corporate sponsor has agreed to match all donations we receive up to $2,000! 🎉
So donate today to amplify your impact—every $1 we receive will turn into $2! 😷
donatemask.ca/fundraiser
#YallMasking #WearAMask
A very generous corporate sponsor has agreed to match all donations we receive up to $2,000! 🎉
So donate today to amplify your impact—every $1 we receive will turn into $2! 😷
donatemask.ca/fundraiser
#YallMasking #WearAMask
August 15, 2025 at 6:17 PM
New fundraiser alert! 📢 Woot woot!
A very generous corporate sponsor has agreed to match all donations we receive up to $2,000! 🎉
So donate today to amplify your impact—every $1 we receive will turn into $2! 😷
donatemask.ca/fundraiser
#YallMasking #WearAMask
A very generous corporate sponsor has agreed to match all donations we receive up to $2,000! 🎉
So donate today to amplify your impact—every $1 we receive will turn into $2! 😷
donatemask.ca/fundraiser
#YallMasking #WearAMask
Reposted by Jeff Gilchrist
Here is your chance to provide constructive feedback on the proposed updated Canadian Standards Association (CSA) respirator standard which calls for universal respirator use in healthcare settings & when performing patient care outside of healthcare settings (eg – in the home).
How you can help:
The draft CSA Z94.4 Standard is now out for Public Review until August 19, 2025.
Please weigh in with your positive, constructive comments at publicreview.csa.ca/Home/View/22... .
Public Review comments are open to everyone who registers.
The draft CSA Z94.4 Standard is now out for Public Review until August 19, 2025.
Please weigh in with your positive, constructive comments at publicreview.csa.ca/Home/View/22... .
Public Review comments are open to everyone who registers.
Log in | CSA Public Review System
publicreview.csa.ca
July 26, 2025 at 1:25 PM
Here is your chance to provide constructive feedback on the proposed updated Canadian Standards Association (CSA) respirator standard which calls for universal respirator use in healthcare settings & when performing patient care outside of healthcare settings (eg – in the home).
Reposted by Jeff Gilchrist
How you can help:
The draft CSA Z94.4 Standard is now out for Public Review until August 19, 2025.
Please weigh in with your positive, constructive comments at publicreview.csa.ca/Home/View/22... .
Public Review comments are open to everyone who registers.
The draft CSA Z94.4 Standard is now out for Public Review until August 19, 2025.
Please weigh in with your positive, constructive comments at publicreview.csa.ca/Home/View/22... .
Public Review comments are open to everyone who registers.
Log in | CSA Public Review System
publicreview.csa.ca
July 25, 2025 at 4:21 PM
How you can help:
The draft CSA Z94.4 Standard is now out for Public Review until August 19, 2025.
Please weigh in with your positive, constructive comments at publicreview.csa.ca/Home/View/22... .
Public Review comments are open to everyone who registers.
The draft CSA Z94.4 Standard is now out for Public Review until August 19, 2025.
Please weigh in with your positive, constructive comments at publicreview.csa.ca/Home/View/22... .
Public Review comments are open to everyone who registers.
Reposted by Jeff Gilchrist
Good News!
Canadian Standards Association (CSA) has called for universal respirator use in healthcare settings & when performing patient care outside of healthcare settings (eg – in the home) in the latest edition of CSA Z94.4, Selection, use and care of filtering respirators.
Canadian Standards Association (CSA) has called for universal respirator use in healthcare settings & when performing patient care outside of healthcare settings (eg – in the home) in the latest edition of CSA Z94.4, Selection, use and care of filtering respirators.
July 25, 2025 at 4:21 PM
Good News!
Canadian Standards Association (CSA) has called for universal respirator use in healthcare settings & when performing patient care outside of healthcare settings (eg – in the home) in the latest edition of CSA Z94.4, Selection, use and care of filtering respirators.
Canadian Standards Association (CSA) has called for universal respirator use in healthcare settings & when performing patient care outside of healthcare settings (eg – in the home) in the latest edition of CSA Z94.4, Selection, use and care of filtering respirators.