> I think since February we’ve learned more and more that people without symptoms are contagious.

Here's an article from January[1]:

> "There's no doubt after reading this paper that asymptomatic transmission is occurring," said Dr. Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases. "This study lays the question to rest."

I've noticed a lot of excuses for poor decisions, as well as rewriting of history that's only a couple of months old. I doubt we're going to see much accountability for the way the pandemic was mishandled.

[1] https://www.cnn.com/2020/01/31/health/coronavirus-asymptomat...

In this case, you can read the email from Dr Robert Kadlec, the US Assistant Secretary for Preparedness and Response at HHS (Edit: provided corrected title), in February that I embedded in my original post

He was shocked to learn of the asymptomatic transmission in mid-late February. This is a key person in determining the US strategy. Not rewriting history, it’s a email that was sent at the time.

As someone else pointed out, that preliminary report from Jan 30 Fauci referred to was debunked within a few days as that specific person actually was showing symptoms.

Not for nothing...that paper was later debunked. Fauci was way out over his skis on that one:

https://www.the-scientist.com/news-opinion/report-of-asympto...

Current thinking is that there's statistical evidence for pre-symptomatic transmission about 2-3 days before symptoms appear:

https://www.sciencedirect.com/science/article/pii/S138665322...

The question then in context become if mask helps during those 2-3 days before symptoms appear. There is a few links above that links to the effectiveness against coughing and sneezing, but I would guess those are symptoms.

Nobody knows. We know that "real" masks (i.e. n95 or better) are effective when worn properly, but many people don't wear them properly.

The evidence for effectiveness of other kinds of masks in the prevention of virus transmission is weak, at best.

Unfortunately, respectable publications have been pushing that paper recently as proof we knew about asymptomatic transmission back in January for stupid, partisan, political reasons.

It's very easy to forget that current decisions and past decisions operate on vastly different kinds of knowledge.

It's easy to look back in time and say "Someone knew the right answer."

It's very hard to stand in the present and say "Of the 20 people who each have a different answer they believe is right, I am going to select the really right one."

Often, the optimal decision is to hedge and delay until information becomes clearer.

Anyone citing that paper recently is being irresponsible. It was debunked about a week after the pre-print went up on the server.

The mortally of corona is minuscule in the 3rd world populations that have born the brunt of previous epidemics.

IT's deadly primarily in populations of people(usually elderly) who can afford the health care needed to keep chronic health issues managed through medication.

the failure of covid-19 to materialize in the slums of Nairobi or poor rural districts of Thailand caused a lot of complacency among western planners who presumed that if it did not hit there it would not affect them.