Catherine Clase
@catherineclase.bsky.social
Professor of medicine, kidney doc, epidemiologist, editor, mask researcher and advocate (airborne)
@docshumanity.bsky.social
Opinions my own
https://www.doctorshumanity.org/petition
https://maskevidence.org
@docshumanity.bsky.social
Opinions my own
https://www.doctorshumanity.org/petition
https://maskevidence.org
Pinned
The idea that 'cloth masks are good only for droplets' still circulates. Many have said this, but it is wrong.
Recommendations about cloth masks, from spring 2020, were based on aerosol evidence
www.acpjournals.org/doi/10.7326/...
#WearTheBestMaskAvailable
1/14
Recommendations about cloth masks, from spring 2020, were based on aerosol evidence
www.acpjournals.org/doi/10.7326/...
#WearTheBestMaskAvailable
1/14
The @uofguelph.bsky.social has canceled the room bookings for People’s Conference for Palestinian Solidarity, which is taking place this weekend.
Organizers are seeking another venue; don’t change your plans if you are coming.
Restriction of freedom of speech on campus is chilling 1/3
Organizers are seeking another venue; don’t change your plans if you are coming.
Restriction of freedom of speech on campus is chilling 1/3
November 27, 2025 at 1:34 PM
The @uofguelph.bsky.social has canceled the room bookings for People’s Conference for Palestinian Solidarity, which is taking place this weekend.
Organizers are seeking another venue; don’t change your plans if you are coming.
Restriction of freedom of speech on campus is chilling 1/3
Organizers are seeking another venue; don’t change your plans if you are coming.
Restriction of freedom of speech on campus is chilling 1/3
Reposted by Catherine Clase
So many eosinophils in this case of tubulointerstitial nephritis secondary to recent antibiotic administration. Few tiny granulomas as well. Eos seen in EM as well. #renalpath #pathsky #nephsky
November 26, 2025 at 11:51 PM
So many eosinophils in this case of tubulointerstitial nephritis secondary to recent antibiotic administration. Few tiny granulomas as well. Eos seen in EM as well. #renalpath #pathsky #nephsky
Reposted by Catherine Clase
Australia recorded ZERO cases of cervical cancer in women under 25 for the first time since they started tracking the cancer in the 80s.
This is the power of vaccines.
The HPV vaccine is extremely effective at preventing cancer.
Viruses can be oncogenic. Get your vaccines and protect yourself!
This is the power of vaccines.
The HPV vaccine is extremely effective at preventing cancer.
Viruses can be oncogenic. Get your vaccines and protect yourself!
newsGP - Australia set for world-first cervical cancer elimination
Vaccination programs have played a key role, and GPs remain ‘instrumental’ in boosting screening rates to reach the 2035 target.
www1.racgp.org.au
November 27, 2025 at 3:45 AM
Australia recorded ZERO cases of cervical cancer in women under 25 for the first time since they started tracking the cancer in the 80s.
This is the power of vaccines.
The HPV vaccine is extremely effective at preventing cancer.
Viruses can be oncogenic. Get your vaccines and protect yourself!
This is the power of vaccines.
The HPV vaccine is extremely effective at preventing cancer.
Viruses can be oncogenic. Get your vaccines and protect yourself!
Reposted by Catherine Clase
Substitute out “gender affirming care” with cancer care.
Or congenital organ defect repair.
Or mental health care.
This isn’t about providing fully informed consequence free care, because that simply doesn’t exist.
It’s about believing trans kids shouldn’t exist.
#abpoli
Or congenital organ defect repair.
Or mental health care.
This isn’t about providing fully informed consequence free care, because that simply doesn’t exist.
It’s about believing trans kids shouldn’t exist.
#abpoli
November 27, 2025 at 3:14 AM
Substitute out “gender affirming care” with cancer care.
Or congenital organ defect repair.
Or mental health care.
This isn’t about providing fully informed consequence free care, because that simply doesn’t exist.
It’s about believing trans kids shouldn’t exist.
#abpoli
Or congenital organ defect repair.
Or mental health care.
This isn’t about providing fully informed consequence free care, because that simply doesn’t exist.
It’s about believing trans kids shouldn’t exist.
#abpoli
The motion was … not unprecedented. Canadian municipalities have consistently taken principled positions on global humanitarian issues. Vancouver condemned South African apartheid in 1989 and implemented ethical procurement policies. 1/2
www.miltontoday.ca/letters-to-t...
www.miltontoday.ca/letters-to-t...
LETTER: Milton council's ruling on Gaza motion truly disappointing
Motion's calls for action not unprecedented, says reader
www.miltontoday.ca
November 26, 2025 at 10:09 PM
The motion was … not unprecedented. Canadian municipalities have consistently taken principled positions on global humanitarian issues. Vancouver condemned South African apartheid in 1989 and implemented ethical procurement policies. 1/2
www.miltontoday.ca/letters-to-t...
www.miltontoday.ca/letters-to-t...
Reposted by Catherine Clase
As we stood in line
at the supermarket
the woman behind me
looked at my mask
and said she was just getting over it,
and the man at the register
said he had it last month,
and the woman in front of me
said she just keeps getting it,
but no one seemed willing
to admit what “it” was.
at the supermarket
the woman behind me
looked at my mask
and said she was just getting over it,
and the man at the register
said he had it last month,
and the woman in front of me
said she just keeps getting it,
but no one seemed willing
to admit what “it” was.
November 25, 2025 at 9:10 PM
As we stood in line
at the supermarket
the woman behind me
looked at my mask
and said she was just getting over it,
and the man at the register
said he had it last month,
and the woman in front of me
said she just keeps getting it,
but no one seemed willing
to admit what “it” was.
at the supermarket
the woman behind me
looked at my mask
and said she was just getting over it,
and the man at the register
said he had it last month,
and the woman in front of me
said she just keeps getting it,
but no one seemed willing
to admit what “it” was.
Reposted by Catherine Clase
Alberta's trans kids & their families need us. We need to show up for them, now. This is our moment to turn the tide.
Join one of our mass organizing calls on Wednesday, November 26th:
5:30 MST - for Albertans
5:30 EST - for everyone else
RSVP: www.momentumcanada.net/AB
Join one of our mass organizing calls on Wednesday, November 26th:
5:30 MST - for Albertans
5:30 EST - for everyone else
RSVP: www.momentumcanada.net/AB
November 19, 2025 at 6:15 PM
Alberta's trans kids & their families need us. We need to show up for them, now. This is our moment to turn the tide.
Join one of our mass organizing calls on Wednesday, November 26th:
5:30 MST - for Albertans
5:30 EST - for everyone else
RSVP: www.momentumcanada.net/AB
Join one of our mass organizing calls on Wednesday, November 26th:
5:30 MST - for Albertans
5:30 EST - for everyone else
RSVP: www.momentumcanada.net/AB
Reposted by Catherine Clase
When LGBTQ+ youth are supported by their parents, that support can literally save lives.
Always show unconditional love and acceptance.
Always show unconditional love and acceptance.
November 23, 2025 at 7:32 PM
When LGBTQ+ youth are supported by their parents, that support can literally save lives.
Always show unconditional love and acceptance.
Always show unconditional love and acceptance.
Reposted by Catherine Clase
iCYMI: "Paris started with periodic, strategic closures of key streets, then day-long closures of the entire city center, always in the context of the conversation about air quality, livability & noise…It's a very smart way of doing it." — @brenttoderian.bsky.social in BlogTO. #Paris
People on board with new solution to Toronto traffic that would limit cars on city streets
Fixing Toronto's gridlock is now so high on the political agenda that the Province is ripping out brand-new bike lanes in a misguided attempt to get …
www.blogto.com
November 23, 2025 at 7:58 PM
iCYMI: "Paris started with periodic, strategic closures of key streets, then day-long closures of the entire city center, always in the context of the conversation about air quality, livability & noise…It's a very smart way of doing it." — @brenttoderian.bsky.social in BlogTO. #Paris
Reposted by Catherine Clase
Keep this in mind when people claim cars mean business — closing Central #Madrid to cars over holidays resulted in a 9.5% boost in retail spending on its main shopping street: STUDY.
There was also a 71% drop in air pollution.
Via @carltonreid.com in @forbes.com. #citymakingmath #citiesforpeople
There was also a 71% drop in air pollution.
Via @carltonreid.com in @forbes.com. #citymakingmath #citiesforpeople
Closing Central Madrid To Cars Resulted In 9.5% Boost To Retail Spending, Finds Bank Analysis
City of Madrid significantly boosted the takings of its shops and restaurants last Christmas by banning cars from the CBD, finds an analysis by Spain's second largest bank.
www.forbes.com
November 20, 2025 at 6:21 AM
Keep this in mind when people claim cars mean business — closing Central #Madrid to cars over holidays resulted in a 9.5% boost in retail spending on its main shopping street: STUDY.
There was also a 71% drop in air pollution.
Via @carltonreid.com in @forbes.com. #citymakingmath #citiesforpeople
There was also a 71% drop in air pollution.
Via @carltonreid.com in @forbes.com. #citymakingmath #citiesforpeople
Reposted by Catherine Clase
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
www.theglobeandmail.com/business/art...
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
www.theglobeandmail.com/business/art...
Is this the moment Canada gets serious about science and the economy?
The federal budget includes $1.7-billion to attract international researchers and support Canadian R&D and IP protections
www.theglobeandmail.com
November 23, 2025 at 8:45 PM
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
www.theglobeandmail.com/business/art...
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
Fund the scientists who are already here. Fund basic science.
www.theglobeandmail.com/business/art...
It’s great when someone you admire for other work speaks truth about Gaza. Thanks @brenttoderian.bsky.social
Airstrikes don’t “test” a ceasefire. They break a ceasefire. Language isn’t that hard, media. Neither is professionalism and bravery.
BREAKING: At least 24 people are dead and 54 wounded after Israeli airstrikes in Gaza, testing the ceasefire that began in October, officials say.
November 23, 2025 at 5:02 AM
It’s great when someone you admire for other work speaks truth about Gaza. Thanks @brenttoderian.bsky.social
Reposted by Catherine Clase
New ChatGPT ad copy: "Shallower than Google"
Relying on ChatGPT to teach you about a topic leaves you with shallower knowledge than Googling and reading about it, according to new research that compared what more than 10,000 people knew after using one method or the other.
Shared by @gizmodo.com: buff.ly/yAAHtHq
Shared by @gizmodo.com: buff.ly/yAAHtHq
November 21, 2025 at 7:01 PM
New ChatGPT ad copy: "Shallower than Google"
Reposted by Catherine Clase
The philosopher invited me
to attend her lecture
on applied ethics
and as I sat in the audience
waiting for it to begin
a man sat down nearby
and asked me why
I was wearing a mask,
and before I could stop myself
I told him:
“I’m applying ethics”
*
297
librarianshipwreck.wordpress.com/2025/11/21/p...
to attend her lecture
on applied ethics
and as I sat in the audience
waiting for it to begin
a man sat down nearby
and asked me why
I was wearing a mask,
and before I could stop myself
I told him:
“I’m applying ethics”
*
297
librarianshipwreck.wordpress.com/2025/11/21/p...
Plague Poems – The Two-Hundred-and-Ninety-Seventh Week
He asked how I was so I replied, “fine, except for the state of the world,” and when I asked how he was he said he too was “fine, except for the state of the world,” and per…
librarianshipwreck.wordpress.com
November 21, 2025 at 9:45 PM
The philosopher invited me
to attend her lecture
on applied ethics
and as I sat in the audience
waiting for it to begin
a man sat down nearby
and asked me why
I was wearing a mask,
and before I could stop myself
I told him:
“I’m applying ethics”
*
297
librarianshipwreck.wordpress.com/2025/11/21/p...
to attend her lecture
on applied ethics
and as I sat in the audience
waiting for it to begin
a man sat down nearby
and asked me why
I was wearing a mask,
and before I could stop myself
I told him:
“I’m applying ethics”
*
297
librarianshipwreck.wordpress.com/2025/11/21/p...
Reposted by Catherine Clase
“She explained how much Covid could hurt her & how vulnerable it felt to be unable to wear a mask to protect herself.
She was a perfect example of why other people need to wear masks even if they don’t personally think Covid will hurt them”
If you want to honour Alice Wong’s memory, please mask up
She was a perfect example of why other people need to wear masks even if they don’t personally think Covid will hurt them”
If you want to honour Alice Wong’s memory, please mask up
Thank You Alice Wong
Alice Wong has passed away and the disability community has lost a leader. I lost a mentor and a friend. The Disabled Ginger wouldn't exist without Alice and everything she taught me.
www.disabledginger.com
November 16, 2025 at 4:48 AM
“She explained how much Covid could hurt her & how vulnerable it felt to be unable to wear a mask to protect herself.
She was a perfect example of why other people need to wear masks even if they don’t personally think Covid will hurt them”
If you want to honour Alice Wong’s memory, please mask up
She was a perfect example of why other people need to wear masks even if they don’t personally think Covid will hurt them”
If you want to honour Alice Wong’s memory, please mask up
Reposted by Catherine Clase
“If I lost everything I would just work harder and take any job to earn it all back”.
Cool story. Try doing that if you’re disabled and bedbound.
You know what often causes people to “lose everything”. Sudden catastrophic health issues.
You can’t “pull yourself up by your bootstraps” when sick.
Cool story. Try doing that if you’re disabled and bedbound.
You know what often causes people to “lose everything”. Sudden catastrophic health issues.
You can’t “pull yourself up by your bootstraps” when sick.
November 19, 2025 at 5:44 PM
Reposted by Catherine Clase
There’s nothing wrong with healthy living.
It just won’t prevent disability. It won’t make you bulletproof.
Telling people to “get healthier” if they want to afford healthcare is effectively telling sick people to accept being left to die.
Healthcare for all.
It just won’t prevent disability. It won’t make you bulletproof.
Telling people to “get healthier” if they want to afford healthcare is effectively telling sick people to accept being left to die.
Healthcare for all.
November 20, 2025 at 11:01 PM
There’s nothing wrong with healthy living.
It just won’t prevent disability. It won’t make you bulletproof.
Telling people to “get healthier” if they want to afford healthcare is effectively telling sick people to accept being left to die.
Healthcare for all.
It just won’t prevent disability. It won’t make you bulletproof.
Telling people to “get healthier” if they want to afford healthcare is effectively telling sick people to accept being left to die.
Healthcare for all.
Reposted by Catherine Clase
Here's a groundbreaking report that examines how countries around the world have successfully expanded abortion access and protected reproductive rights. The reports offer U.S.-based policymakers proven strategies to counter restrictions and treat abortion as essential health care.
New Reports Bring Global Solutions to Bolster U.S. Lawmakers in the Fight to Protect Reproductive Freedom - O'Neill
WASHINGTON, D.C. – Today, the State Innovation Exchange (SiX) and the O’Neill Institute for National and Global Health, released Beyond Borders, a groundbreaking report series that examines how countr...
oneill.law.georgetown.edu
November 21, 2025 at 3:14 AM
Here's a groundbreaking report that examines how countries around the world have successfully expanded abortion access and protected reproductive rights. The reports offer U.S.-based policymakers proven strategies to counter restrictions and treat abortion as essential health care.
Reposted by Catherine Clase
Poverty and disability often go together.
It’s difficult to “try harder” your way out of financial problems when you lose your health.
The pull yourselves up by your bootstrap mentality goes out the window if you’re bedbound.
It can happen to anyone at any time.
They aren’t moral failings.
It’s difficult to “try harder” your way out of financial problems when you lose your health.
The pull yourselves up by your bootstrap mentality goes out the window if you’re bedbound.
It can happen to anyone at any time.
They aren’t moral failings.
November 21, 2025 at 3:45 AM
Poverty and disability often go together.
It’s difficult to “try harder” your way out of financial problems when you lose your health.
The pull yourselves up by your bootstrap mentality goes out the window if you’re bedbound.
It can happen to anyone at any time.
They aren’t moral failings.
It’s difficult to “try harder” your way out of financial problems when you lose your health.
The pull yourselves up by your bootstrap mentality goes out the window if you’re bedbound.
It can happen to anyone at any time.
They aren’t moral failings.
Reposted by Catherine Clase
The govt is betraying its promise to Canadians.
The minister promised new coal mine selenium regulations to protect our rivers and lakes. Now, instead of providing protection, the Liberals are allowing a dramatic increase in the pollutants going into rivers and lakes.
The minister promised new coal mine selenium regulations to protect our rivers and lakes. Now, instead of providing protection, the Liberals are allowing a dramatic increase in the pollutants going into rivers and lakes.
November 20, 2025 at 5:25 PM
The govt is betraying its promise to Canadians.
The minister promised new coal mine selenium regulations to protect our rivers and lakes. Now, instead of providing protection, the Liberals are allowing a dramatic increase in the pollutants going into rivers and lakes.
The minister promised new coal mine selenium regulations to protect our rivers and lakes. Now, instead of providing protection, the Liberals are allowing a dramatic increase in the pollutants going into rivers and lakes.
@aslamrana.bsky.social, thank you for standing with
@heathermcpherson.bsky.social, Nate Erskine-Smith and other principled MPs in jointly seconding @jennykwan.bsky.social's "No More Loopholes" bill. Let's all work to stop the US from controlling where Canadian arms end up in the world.
@heathermcpherson.bsky.social, Nate Erskine-Smith and other principled MPs in jointly seconding @jennykwan.bsky.social's "No More Loopholes" bill. Let's all work to stop the US from controlling where Canadian arms end up in the world.
November 20, 2025 at 9:55 PM
@aslamrana.bsky.social, thank you for standing with
@heathermcpherson.bsky.social, Nate Erskine-Smith and other principled MPs in jointly seconding @jennykwan.bsky.social's "No More Loopholes" bill. Let's all work to stop the US from controlling where Canadian arms end up in the world.
@heathermcpherson.bsky.social, Nate Erskine-Smith and other principled MPs in jointly seconding @jennykwan.bsky.social's "No More Loopholes" bill. Let's all work to stop the US from controlling where Canadian arms end up in the world.
Join Amnesty International in demanding the immediate release of Sonia Dahmani and an end to her cruel treatment. Sonia is a courageous Tunisian lawyer and human rights defender, has been jailed for speaking out against injustice.
takeaction.amnesty.ca/page/178194/...
takeaction.amnesty.ca/page/178194/...
Write for Rights: Demand the Release of Human Rights Defender Sonia Dahmani!
Demand the immediate release of Sonia Dahmani and an end to her cruel treatment, as she is being held in rat-infested conditions without proper medical care. Sonia is a courageous Tunisian lawyer and ...
takeaction.amnesty.ca
November 17, 2025 at 10:24 PM
Join Amnesty International in demanding the immediate release of Sonia Dahmani and an end to her cruel treatment. Sonia is a courageous Tunisian lawyer and human rights defender, has been jailed for speaking out against injustice.
takeaction.amnesty.ca/page/178194/...
takeaction.amnesty.ca/page/178194/...
Canadians and trans-allies with Canadian followers: I just signed this important petition reaffirming Canada as a safe haven for 2SLGBTQIA+ refugees. Will you join me; will you share this post?
www.ourcommons.ca/petitions/en...
www.ourcommons.ca/petitions/en...
Sign this Petition - Petitions
www.ourcommons.ca
November 17, 2025 at 8:48 PM
Canadians and trans-allies with Canadian followers: I just signed this important petition reaffirming Canada as a safe haven for 2SLGBTQIA+ refugees. Will you join me; will you share this post?
www.ourcommons.ca/petitions/en...
www.ourcommons.ca/petitions/en...
Reposted by Catherine Clase
“The rise in high-fronted SUVs poses a clear and growing threat to public safety, especially for children,” states the report. “With no benefit to society, it’s time for lawmakers at all levels to act.” Via @carltonreid.com in @forbes.com.
Cap SUV/truck hood heights. And ban unsafe designs.
Cap SUV/truck hood heights. And ban unsafe designs.
EU Must Cap SUV Hood Heights Urges Report. Crash Test Body Says Not As Simple As That
Higher fronts on cars significantly increase the death rate when pedestrians and cyclists are struck, says new report. EuroNCAP says more complex than that.
www.forbes.com
November 15, 2025 at 7:18 AM
“The rise in high-fronted SUVs poses a clear and growing threat to public safety, especially for children,” states the report. “With no benefit to society, it’s time for lawmakers at all levels to act.” Via @carltonreid.com in @forbes.com.
Cap SUV/truck hood heights. And ban unsafe designs.
Cap SUV/truck hood heights. And ban unsafe designs.