/opinion

Opinion | Yes, the #Coronavirus Is in the Air - The New York Times
▻https://www.nytimes.com/2020/07/30/opinion/coronavirus-aerosols.html

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I agree that long-range transmission by aerosols probably is not significant, but I believe that, taken together, much of the evidence gathered to date suggests that close-range transmission by #aerosols is significant — possibly very significant, and certainly more significant than direct droplet spray.

The practical implications are plain:

Social distancing really is important. It keeps us out of the most concentrated parts of other people’s respiratory plumes. So stay away from one another by one or two meters at least — though farther is safer.

Wear a mask. Masks help block aerosols released by the wearer. Scientific evidence is also building that masks protect the wearer from breathing in aerosols around them.

When it comes to masks, size does matter.

The gold standard is a N95 or a KN95 respirator, which, if properly fitted, filters out and prevents the wearer from breathing in at least 95 percent of small aerosols.

The efficacy of surgical masks against aerosols varies widely.

One study from 2013 found that surgical masks reduced exposure to flu viruses by between 10 percent and 98 percent (depending on the mask’s design).

A recent paper found that surgical masks can completely block seasonal coronaviruses from getting into the air.

To my knowledge, no similar study has been conducted for #SARS-CoV-2 yet, but these findings might apply to this virus as well since it is similar to seasonal coronaviruses in size and structure.

My lab has been testing cloth masks on a mannequin, sucking in air through its mouth at a realistic rate. We found that even a bandanna loosely tied over its mouth and nose blocked half or more of aerosols larger than 2 microns from entering the mannequin.

We also found that especially with very small aerosols — smaller than 1 micron — it is more effective to use a softer fabric (which is easier to fit tightly over the face) than a stiffer fabric (which, even if it is a better filter, tends to sit more awkwardly, creating gaps).

Avoid crowds. The more people around you, the more likely someone among them will be infected. Especially avoid crowds indoors, where aerosols can accumulate.

Ventilation counts. Open windows and doors. Adjust dampers in air-conditioning and heating systems. Upgrade the filters in those systems. Add portable air cleaners, or install germicidal ultraviolet technologies to remove or kill virus particles in the air.

It’s not clear just how much this coronavirus is transmitted by aerosols as opposed to droplets or via contact with contaminated surfaces. Then again, we still don’t know the answer to that question even for the flu, which has been studied for decades.

But by now we do know this much: Aerosols matter in the transmission of #Covid-19 — and probably even more so than we have yet been able to prove.

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Opinion | John Lewis: Together, You Can Redeem the Soul of Our Nation - The New York Times
▻https://www.nytimes.com/2020/07/30/opinion/john-lewis-civil-rights-america.html

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By John Lewis

Mr. Lewis, the civil rights leader who died on July 17, wrote this essay shortly before his death, to be published upon the day of his funeral.

July 30, 2020

While my time here has now come to an end, I want you to know that in the last days and hours of my life you inspired me. You filled me with hope about the next chapter of the great American story when you used your power to make a difference in our society. Millions of people motivated simply by human compassion laid down the burdens of division. Around the country and the world you set aside race, class, age, language and nationality to demand respect for human dignity.

That is why I had to visit Black Lives Matter Plaza in Washington, though I was admitted to the hospital the following day. I just had to see and feel it for myself that, after many years of silent witness, the truth is still marching on.

Emmett Till was my George Floyd. He was my Rayshard Brooks, Sandra Bland and Breonna Taylor. He was 14 when he was killed, and I was only 15 years old at the time. I will never ever forget the moment when it became so clear that he could easily have been me. In those days, fear constrained us like an imaginary prison, and troubling thoughts of potential brutality committed for no understandable reason were the bars.

Though I was surrounded by two loving parents, plenty of brothers, sisters and cousins, their love could not protect me from the unholy oppression waiting just outside that family circle. Unchecked, unrestrained violence and government-sanctioned terror had the power to turn a simple stroll to the store for some Skittles or an innocent morning jog down a lonesome country road into a nightmare. If we are to survive as one unified nation, we must discover what so readily takes root in our hearts that could rob Mother Emanuel Church in South Carolina of her brightest and best, shoot unwitting concertgoers in Las Vegas and choke to death the hopes and dreams of a gifted violinist like Elijah McClain.

Like so many young people today, I was searching for a way out, or some might say a way in, and then I heard the voice of Dr. Martin Luther King Jr. on an old radio. He was talking about the philosophy and discipline of nonviolence. He said we are all complicit when we tolerate injustice. He said it is not enough to say it will get better by and by. He said each of us has a moral obligation to stand up, speak up and speak out. When you see something that is not right, you must say something. You must do something. Democracy is not a state. It is an act, and each generation must do its part to help build what we called the Beloved Community, a nation and world society at peace with itself.

Ordinary people with extraordinary vision can redeem the soul of America by getting in what I call good trouble, necessary trouble. Voting and participating in the democratic process are key. The vote is the most powerful nonviolent change agent you have in a democratic society. You must use it because it is not guaranteed. You can lose it.

You must also study and learn the lessons of history because humanity has been involved in this soul-wrenching, existential struggle for a very long time. People on every continent have stood in your shoes, through decades and centuries before you. The truth does not change, and that is why the answers worked out long ago can help you find solutions to the challenges of our time. Continue to build union between movements stretching across the globe because we must put away our willingness to profit from the exploitation of others.

Though I may not be here with you, I urge you to answer the highest calling of your heart and stand up for what you truly believe. In my life I have done all I can to demonstrate that the way of peace, the way of love and nonviolence is the more excellent way. Now it is your turn to let freedom ring.

When historians pick up their pens to write the story of the 21st century, let them say that it was your generation who laid down the heavy burdens of hate at last and that peace finally triumphed over violence, aggression and war. So I say to you, walk with the wind, brothers and sisters, and let the spirit of peace and the power of everlasting love be your guide.

#John_Lewis #Black_lives_matter #Droits_civiques #Démocratie