Louise Hidinger, PhD

Since measles is coming back, here's a question:

What is the "half-life" of airborne decay of measles?

Answer: We have no idea. People think it's long (1 to 2 hours).

Why don't we know? Funders largely felt there wasn't a need to measure it since it was managed with vaccines.

Airborne transmission of respiratory viruses A Review discusses the scientific basis of and factors controlling airborne transmission of respiratory viruses including coronavirus.

Amazing that this review paper from 2021 just became my most cited paper of my 30+ yr career. I am honored to have been the lead first co-corresponding author with @ChiaWang8. COVID is indeed airborne--as are most other respiratory viruses. @ucsandiego.bsky.social

www.science.org/doi/full/10....

Here's an easy way to select a minimum clean air delivery rate (CADR) when you're shopping for a portable air cleaner (filter).

For example, if my room is 15 ft x 12 ft = 180 sq ft, then I'd want a CADR of at least 120 CFM (cubic feet per minute).

Signed - thanks for sharing this!

Thanks for boosting!! Just an fyi that the closing date of CIATO's petition is Monday January 12 😊

Help let the feds know we need them to step up now to protect the Canada Healthcare Act - a source of great pride in Canada.

‼️Deadline to sign is Jan. 16, 4:00pm!‼️

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

#MakeYourNoise
#NoTo2TierCare

/fin

Thanks for boosting! Getting the Health Canada IAQ guidance put into action would be a big first step towards a protective IAQ policay and better ventilation for all!

Toronto Board of Health Advocacy-CIATO We have over 750 signatures, help us get to our next goal of 800! Join Clean Indoor Air Toronto in sending a clear message to the City of Toronto that you want a city that’s healthier, more accessib...

Adopting Health Canada’s indoor air quality guidelines would significantly improve public health while strengthening accessibility and climate resilience across Toronto. I encourage residents to join @CleanIndoorAirTO and tell the City you support a healthier, future-ready Toronto.
bit.ly/ciatodec25

We’re over 600 signatures, hoping to get to 1000 before the Board of Health meets Monday. You don’t need to live in Toronto to sign! #topoli #cleantheair

❤️Open to all signatories❤️

Deadline Jan 12

Petition to adopt Health🇨🇦's new IAQ Guidance:
bsky.app/profile/mama...

No IAQ policy at any level of govt ensuring indoor air is clean & safe to breathe atm

Clean air for kids & staff in schools & daycares shouldn’t be controversial

🙏✍️&share

Thank you

I'll just leave this 2018 paper here:

academic.oup.com/jid/article/...

also, we have covid and influenza still causing outbreaks on hospital units. Unforced error! We should have near-zero or zero Hospital-acquired infections. Respiratory infections (including influenza and COVID) are predominantly spread by airborne means
10/

Masks work! respirator masks work even better. If you are vulnerable wear a mask to protect yourself. If you are sick, wear a mask, or better yet stay at home and avoid making your fellow citizens sick as well.
8/

We need a Christmas miracle. Please sign and share! 👇👇👇 #CleanAir for all!

SARS-CoV-2 is so dangerous precisely because of its insidious nature. Its propensity to continually re-infect. The superficial similarity of the symptoms it causes to those of other common viruses. The unseen risk of sequelae. That wretched molecular shark tricks almost everyone.

Schools have become cesspools for cold and flu, but they don't have to be: Ontario School Safety The volunteer organization Ontario School Safety is calling on the provincial government to improve air quality in schools as flu spreads.

After the devastating loss of the 3 children in Ottawa, it was urgent to get info out re the additional ways avail to protect one’s loved ones from serious illness as we enter the holidays…

and to remind young fams this amt of sickness ISN’T normal.

#VaccinePlus

ottawa.citynews.ca/2025/12/21/s...

Thanks for the boost!! Everyone deserves #cleanindoorair!

Toronto Board of Health Advocacy-CIATO Join Clean Indoor Air Toronto in sending a clear message to the City of Toronto that you want a city that’s healthier, more accessible, and better prepared for the future! Tell the Board of Health to...

Join Clean Indoor Air Toronto in sending a clear message to the City of Toronto that you want a city that’s healthier, more accessible, and better prepared for the future!

Tell the Board of Health to direct Toronto Public Health to take steps to adopt Health Canada’s new guidelines for indoor air.

Toronto Board of Health Advocacy-CIATO We have over 315 signatures, help us get to our next goal of 325! Join Clean Indoor Air Toronto in sending a clear message to the City of Toronto that you want a city that’s healthier, more accessib...

Join Clean Indoor Air Toronto in sending a clear message to City of Toronto that you want a city that’s healthier, more accessible, & better prepared for the future! Tell the Board of Health to direct Toronto Public Health to take steps to adopt Health Canada’s new IAQ guidance. bit.ly/ciatodec25

Did the climate world misread Carney? Many in the climate movement saw a fellow traveller in Mark Carney — the man who could preach climate action in the language of finance — but what if they were wrong from the very start?

The way to read the Canada-Alberta MOU is that Carney is using the Trump effect as political cover to pursue the deregulatory agenda he’s long wanted. I spoke with @naomiaklein.bsky.social who called it a classic example of the shock doctrine.

“Right now, we’re in the thick of COVID-19. We know that COVID-19 is actively circulating in our province…it’s been increasing since late summer”

No kidding. It's gross NS Health didn't warn people sooner. And, hand-washing doesn't prevent airborne spread. Please wear a mask & get vaccinated.

The CSA’s revised standard on respirators should help us all breathe easier New draft standards for respirator use recognize the importance of protecting workers and patients in health-care settings, where there is a higher risk of pathogen exposure

theconversation.com/the-csas-rev...

Aranet4 CO2 ppm graphic including the Watch Party at Rogers Centre on Wednesday and Game 6 of the World Series yesterday. Yesterday's peak CO2 ppm maxed out at 2099 indicating very poor air quality and reflecting a high risk of breathing in airborne pathogens (including SARSCoV2, Measles, Pertussis, Influenza....). #MasksWork #CovidKills #StillAPandemic.

Once again imploring you, at least if you're going into crowds, to wear a well-fitting respirator. The airborne illnesses that are felling Blue Jays fans as I type are no joke. The air quality at Rogers Centre is shockingly bad. Airborne viruses can kill and disable even the "healthy".

I just want to make this *abundantly clear*.

When “experts” say COVID-19 is mild for kids…

THEY HAD, AND HAVE NO IDEA WHAT TEN YEARS WORTH OF INFECTIONS WILL CAUSE.

Faces of evil.

Far too many Canadians think the federal government controls everything. All while ignoring the decades-long sabotage of 🇨🇦 by powerful provincial gov’ts that control healthcare, education, minimum wage, rent controls, infrastructure & so many other aspects of gov’t that impact daily life. #cdnpoli

Scientists develop first ‘accurate blood test’ to detect chronic fatigue syndrome Research could offer hope for ME patients – but some experts urge caution and say more studies needed

ME/CFS is a devastating condition that has long been denied, dismissed, psychologised and underdiagnosed. Research is at last starting to catch up with it, with glimmers of hope for those who have been left untreated for so long.
There's a huge BUT coming ...🧵
www.theguardian.com/society/2025...

The Effect of Air Purifiers in Schools The Effect of Air Purifiers in Schools

Here's the link to working paper mentioned above:

The Effect of Air Purifiers in Schools (June 11, 2025)
www.rff.org/publications...

Screenshot of a study summary. It says air purifiers were installed in primary school classrooms to reduce children’s exposure to air pollution. The intervention reduced indoor PM₂.₅ by 32% and student absenteeism by 12.5%. It notes larger effects for students with higher absence before treatment, stronger impact when outdoor air pollution was lower, and smaller impact when outdoor pollution was high. Students reported fewer breathing problems and greater awareness of air quality. The cost per avoided missed school day was about €11, with a cost-benefit ratio of one-to-nine.

Air purifiers cut missed school days by 12.5%. 💪