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Catherine Clase

@catherineclase.bsky.social

4.6K followers 1.4K following 460 posts

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

www.doctorshumanity.org

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Catherine Clase @catherineclase.bsky.social · Jan 21

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
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Cloth can block droplets and aerosols, and layers add efficiency. Filtration efficiency for single layers of different types of cotton cloth in a bioaerosol (0.2 µm) experiment was between 43% and 94%, compared with 98% to 99% for fabric from disposable medical masks (2). In a summary of similar observations, single layers of scarfs, sweatshirts, T-shirts, and towels were associated with filtration efficiency of 10% to 40% in experiments using NaCl aerosol (0.075 µm) (3). For tea towel fabric, studied with aerosol-sized particles, filtration efficiency in experiments using a bacterial marker was 83% with 1 layer and 97% with 2 layers, compared with 96% for a medical mask (4). In experiments using virus, 1 layer of tea towel had 72% efficiency and 1 layer of T-shirt fabric 51%, compared with 90% for a medical mask (4). A 2020 study confirms that some fabrics block clinically useful percentages of transmission, even for aerosols and even in single layers; multiple layers improve efficiency (5).

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Reposted by Catherine Clase

dr. caitlin m. green @caitlinmoriah.bsky.social · 22h

there are SO many more inflatable costumes tonight. clearly we have settled on a motif

Wide shot of many people in inflatable costumes

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Catherine Clase @catherineclase.bsky.social · 3d

#nephsky

www.thelancet.com/journals/lan...

Oral iptacopan therapy in patients with C3 glomerulopathy: a randomised, double-blind, parallel group, multicentre, placebo-controlled, phase 3 study

Iptacopan showed a statistically significant, clinically meaningful proteinuria reduction in addition to RAAS inhibitors and immunosuppression at 6 months. Iptacopan was well tolerated with an accepta...

www.thelancet.com

Reposted by Catherine Clase

Plague Poems @plaguepoems.bsky.social · 7d

A friend says
it is always the right time
to resist
oppression.

A friend says
it is always the right time
to resist
surveillance.

A friend says
it is always the right time
to resist
fascism.

Yes, my friends, and
it is always the right time
to resist
infection.

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Reposted by Catherine Clase

Plague Poems @plaguepoems.bsky.social · 10d

I keep hearing people say
that this
is just that time of the year
when everyone
has a cough,
and though I am not very old
I am old enough to remember
that this
has not always been
a time of the year
when everyone
has a cough.

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Catherine Clase @catherineclase.bsky.social · 8d

#HamOnt

A blue background, see, distant light green hills, beyond that blue sky with a few fluffy white clouds. Central, a small yacht with 3 white sails, no people, is refected in the water.

Text reads (back on pale blue)

In support of the freedom flotilla and the arrests by the IOF of its occupants

Bring a flag, a banner, sign, or just yoursel

Meet at Hamilton city hall 3pm Thurs oct 2

@mivasair.bsky.social

Catherine Clase @catherineclase.bsky.social · 8d

New Canadian action item @heathermcpherson.bsky.social petition to expedite visas and to treat would-be refugees from Gaza as refugees from the Ukraine were treated

www.ourcommons.ca/petitions/en...

8/7 :)

www.ourcommons.ca

Catherine Clase @catherineclase.bsky.social · 10d

Mohammad Zubairi, a developmental paediatrician, reflects on Orange Shirt Day and telling children the truth about the past

archive.is/EsjSM

archive.is

Reposted by Catherine Clase

Tara Moriarty @moriartylab.bsky.social · 10d

Canadian COVID Forecast: Sep 27 - Oct 10, 2025

SEVERE: none
VERY HIGH: MB, NL, NS, SK
HIGH: CAN, AB, BC, NB, North, ON, PEI, QC,
MODERATE: none

About 1 in 60 people in Canada are CURRENTLY infected.

This image shows gauges with the Sep 27 - Oct 10, 2025 Forecast scores for Canada, the provinces, & territories. From left to right:

Canada: HIGH - 7.5
Alberta: HIGH - 6
British Columbia: HIGH - 5.8
Manitoba: VERY HIGH - 12.1
New Brunswick: HIGH - 6.3
Newfoundland & Labrador: VERY HIGH - 10.2
North: HIGH - 9.2
Nova Scotia: VERY HIGH - 11.6
Ontario: HIGH - 6.3
Prince Edward Island: HIGH - 7
Quebec: HIGH - 9.6
Saskatchewan: VERY HIGH - 12.4

A text box reads: "The COVID Forecast is calculated from 3 equally weighted categories: 1) Current infections and spread; 2) Healthcare system impact; 3) Mortality. Within each category, there is one sub-category for trends over the most recent week (Trends) and one sub-category for current parameter values relative to a specified baseline (Current values). Trends and current values are weighted equally when determining the final score for a category. All Forecast input data and sources are available here (https://datastudio.google.com/embed/u/0/reporting/42b886cf-d661-488e-b7d8-5c5836b55ab6/page/p_2yqs028mwc). Past Forecast scores are available in the table below. Forecast scores are grouped into 4 ranges: MODERATE (1 to <5, white), HIGH (6 to <10, yellow), VERY HIGH (10 to <15, orange), SEVERE (>15 red)."

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Catherine Clase @catherineclase.bsky.social · 11d

Petition e-6834 - Petitions

www.ourcommons.ca

Catherine Clase @catherineclase.bsky.social · 11d

Insightful 5 min read

🎃🪦 BLOODSUGARSETHMASKET 🪦🎃 @smotus.bsky.social · 11d

@nberlat.bsky.social: “Comey was arguably one of the first consequential establishment figures to comply in advance with Donald Trump. For his trouble, and his pivotal role in vaulting Trump to power, he has now been targeted by Trump’s Justice Department for a politically motivated indictment.”

Comey and the lesson of pre-capitulation

He tried to palliate bad faith Republicans. Now we're all paying the price.

open.substack.com

Reposted by Catherine Clase

Doctora Malka Older @older.bsky.social · 12d

Translation: "I arrived in Bogotá. I no longer have a visa to travel to the USA. I don't care," responded the Colombian president. "The seat of the United Nations cannot continue in New York," he added.

Doctora Malka Older @older.bsky.social · 12d

""Llegué a Bogotá. Ya no tengo visa para viajar a EE.UU. No me importa", reaccionó el presidente colombiano. "La sede de Naciones Unidas no puede continuar en Nueva York", agregó."

Petro responde a EE.UU. que la retirada de su visa viola el derecho internacional y las normas de inmunidad de la ONU

"Llegué a Bogotá. Ya no tengo visa para viajar a EE.UU. No me importa", reaccionó el presidente colombiano. "La sede de Naciones Unidas no puede continuar en Nueva York", agregó. EE.UU. dice que instó...

www.telemundo.com

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Reposted by Catherine Clase

Tara Chang @taraichang.bsky.social · 11d

Stanford Nephrology is hiring! We are hiring a full-time faculty in the Clinician Educator line. Interest in onco-neph a strong plus. More information available here: med.stanford.edu/nephrology/j...

Clinician Educator

med.stanford.edu

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Reposted by Catherine Clase

Joel Topf @kidneyboy.bsky.social · 11d

Interesting case from the Skeleton Key Group which just keeps pumping out the #FOAMed

www.renalfellow.org/2025/09/28/s...

Skeleton Key Group Case #40: Cosmetic Calcium

Author: Nikitha (Niki) Cherayil, MD A. The Stem A middle-aged woman with chronic kidney disease stage 3 in the setting of hypertension and recurrent kidney st

www.renalfellow.org

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Reposted by Catherine Clase

Joel Topf @kidneyboy.bsky.social · 13d

I did a blog post about Apple's new Hypertension Detection System

pbfluids.com/2025/09/appl...

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Catherine Clase @catherineclase.bsky.social · 12d

Your petition isn't signed until you verify your identity by clicking the link in the confirmation email

This means you can't sign it twice by accident

And you have a record of having signed it

Kudos to all these petition writers and sponsoring MPs

7/7

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Catherine Clase @catherineclase.bsky.social · 12d

Salma Zahid's petition to enact a loophole-free two-way arms embargo, end Canada's free trade agreement with Isr..l, and investigate and prosecute those responsible for war crimes

6/7

www.ourcommons.ca/petitions/en...

www.ourcommons.ca

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Catherine Clase @catherineclase.bsky.social · 12d

@gordjohns.bsky.social's petition to request access for UN and other humanitarian agencies

5/7

www.ourcommons.ca/petitions/en...

www.ourcommons.ca

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Catherine Clase @catherineclase.bsky.social · 12d

@elizabethemay.bsky.social's petition to use diplomatic and economic pressure to end the siege

4/7

www.ourcommons.ca/petitions/en...

www.ourcommons.ca

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Catherine Clase @catherineclase.bsky.social · 12d

Read more about 'Uniting for Peace' here:

lifelineforpalestine.com

3/7

Lifeline for Palestine

Join Lifeline for Palestine to end the genocide now. Register for our webinar to learn more and spread awareness. Lifeline for Palestine Uniting For Peace Resolution

lifelineforpalestine.com

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Catherine Clase @catherineclase.bsky.social · 12d

This is @heathermcpherson.bsky.social's petition asking the Canadian government to invoke 'Uniting for Peace' at the UN General Assembly

If passed, this permits the implementation of a multi-lateral peace-keeping force. Avoids the security council veto

2/7

www.ourcommons.ca/petitions/en...

www.ourcommons.ca

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Catherine Clase @catherineclase.bsky.social · 12d

Canadians of conscience: signatures on e-petitions are not public.

"... signatures are not made public, even to the sponsoring Member or the Member who had presented the petition to the House." www.ourcommons.ca/procedure/pr...

Whatever your role, you can sign these as a citizen👇
1/7

Presentation of Petitions - Public Petitions - House of Commons Procedure and Practice, Third edition, 2017 - ProceduralInfo - House of Commons of Canada

www.ourcommons.ca

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Reposted by Catherine Clase

Kelly @broadwaybabyto.bsky.social · 12d

A gunman opened fire on a waterfront bar from a boat.

Another opened fire on a Mormon church.

The problem is the guns.

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Catherine Clase @catherineclase.bsky.social · 12d

In a world full of things that demand your attention, take a second to oppose the sickening idea of octopus farming

secure.avaaz.org/campaign/en/...

Octopus massacre

They're building the world’s first octopus farm. Here's how we can stop them:

secure.avaaz.org

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Reposted by Catherine Clase

Cycle Fun Montreal @cyclefunmontreal.bsky.social · 24d

"A 2025 CAA survey found 73% of drivers slowed down when approaching an Automated Speed Enforcement (ASE) camera."
So 27% didn't slow down after passing a "speed camera ahead" sign, and got a ticket.
They deserved the ticket, just like the rest of us deserve safe streets.

As a former traffic cop, I see the evidence first-hand – speed cameras aren’t a tax grab, they make cities safer

When Ontario Premier Doug Ford called automated speed enforcement cameras a tax grab and said municipalities should get rid of them, I was shocked, write Sean Shapiro

www.theglobeandmail.com

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Reposted by Catherine Clase

Charlie Angus @charlieangus104.bsky.social · 14d

Dear Bob Rae,
You don't get paid to sit and listen. You get paid to stand up for Canadian values.
During the brutal Russian invasion of Ukraine you used the word genocide numerous times.
The UN has found Israel guilty of genocide.
You're our ambassador.
Why the silence?

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