Why I believe it is simultaneously true that masks work and mask mandates do not work. The reasons form the basis for our ability to move forward together. A long🧵

First, masks. I don’t pay attention to simulations and mannequin studies. Those of us who write COVID policies for healthcare settings started with this systematic review and meta-analysis which used data from COVID and other 🦠s.

N95s were in disgustingly short supply that first spring. Many hospitals reserved them for COVID patients undergoing high risk procedures only. We wore surgical 😷 for the rest. And we found something amazing: HCWs weren’t higher risk than other essential workers.

Despite prolonged close contact (we practically bathe in 🦠 all day), seroprevalence rates among HCWs were consistent with the surrounding community, and patient facing HCW were not at greater risk than non patient facing. @ericashenoy summarized it in these slides in 2020.

Little known fact: the patients, for the most part, are not wearing masks. One-way masking is how we have always used them. On the sick person or the HCW, not both. Oh, and if you’re worried the holes are too big? That’s ok. The electrostatic charge is part of the mechanism.

c. People aren’t wearing them right d. It’s not realistic to expect that people keep a mask on all the time, because they need to eat and drink (traveled by air before the mandate lifted? people are eating and drinking every second in airport and plane)

That’s not to say that we need to tighten the mandate & require continuous wearing of N95s. Countries/cities/schools with mandates haven’t had different shaped curves than those without, even if they required N95s. Plus if you mandate medical grade PPE, you’d better provide it.

What does this mean? It means mandates are not effective or necessary, even when cases are rising. They cause rifts in society for no reason. If you’re high-risk or risk averse, a medical grade mask will protect you as well as it would if others were wearing it too.

@JenniferNuzzo in this @landmanspeaking interview hit the nail on the head. There are more important things we should do to protect the public, like vaccinations and testing to treat.

Getting COVID is inevitable, so I’m not willing to hide my face forever. Let’s get back to a place of mutual respect. Of evidence-based science rather than ideology. *That* is how we take care of each other.

@ShiraDoronMD a breath of fresh air....

@ShiraDoronMD Yes. This. Even effective masking is only as effective of one's commitment to doing it religiously around everyone, including (especially) familiar company.

@ShiraDoronMD Masks don’t work though.

@ShiraDoronMD Ventilation is important, some people don't care much for ventilation, either, particularly in winter. Consider keeping rooms well ventilated, or not gathering indoors, not gathering in large numbers. Avoid sitting for two hours in a room where 60 people are practicing choir.

@ShiraDoronMD Reasons a,b,c,d seem weak and/or fixable. They all seem to be of the form: if it can't be done perfectly 100% of the time, it isn't worth doing.

@ShiraDoronMD How are you even a doctor??? A person without a mask coughed directly in front of me at A GROCERY store, now I am suffering the worst of #LongCovid . Due to Covid I have Gastroparesis and part intestine removed!! MEANING I can NO longer eat normal food! Liquid diet only!!!🤬

@ShiraDoronMD It's not perfect!!! So why even bother!!! Is a fantastic take from an epidemiologist...

@ShiraDoronMD Disagree. Spread has greatly increased with great unmasking.

@ShiraDoronMD Spread happened in places where we took off our masks because we took off our masks. Taking off our masks in crowded indoor places accelerates the spread. We do need to upgrade masks. Many places now require that you wear a high quality mask.

@ShiraDoronMD @Mediadisdat Wait, cloth masks don't work? Are there any washable or reusable masks which do?