You want science.  You always state that.  Well, here is your very own science.

The reference is: "Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings---Personal Protective and Environmental Measures."  Published in: "Emerging Infectious Diseases, Vol.26, No. 5, May 2020."  (That journal is published by the CDC.)

I quote from the abstract: "Here, we review the evidence base on the effectiveness of nonpharmaceutical personal protective measures and environmental hygiene measures in non-healthcare settings and discuss their potential inclusion in pandemic plans. Although mechanistic studies [*] support the potential effect of hand hygiene or face masks, evidence from 14 randomized controlled trials of these measures did not support a substantial effect on transmission of laboratory-confirmed influenza. We similarly found limited evidence on the effectiveness of improved hygiene and environmental cleaning."

Here are quotes from pages 970-972 of the review: "In our systematic review, we identified 10 RCTs [randomized controlled trials] that reported estimates of the effectiveness of face masks in reducing laboratory-confirmed influenza virus infections in the community from literature published during 1946-July 27, 2018. In pooled analysis, we found no significant reduction in influenza transmission with the use of face masks..."

"Disposable medical masks (also known as surgical masks) are loose-fitting devices that were designed to be worn by medical personnel to protect accidental contamination of patient wounds, and to protect the wearer against splashes or sprays of bodily fluids... There is limited evidence for their effectiveness in preventing influenza virus transmission either when worn by the infected person for source control or when worn by uninfected persons to reduce exposure. Our systematic review found no significant effect of face masks on transmission of laboratory-confirmed influenza."

"In this review, we did not find evidence to support a protective effect of personal protective measures or environmental measures in reducing influenza transmission."

"We did not find evidence that surgical-type face masks are effective in reducing laboratory-confirmed influenza transmission, either when worn by infected persons (source control) or by persons in the general community to reduce their susceptibility..."

[*] In case you want to quibble about the value of what the authors refer to as "mechanistic studies," the authors are correctly setting those studies off to the side, in favor of the material they preferred to examine: randomized controlled trials---which are widely considered to be more valuable, relevant, and meaningful.

So there you have it.

Your science.

Take off your masks.  Governors and mayors and presidents and prime ministers, cancel the orders to wear masks.  You're non-scientific.  In the extreme.

SOURCE:

wwwnc[dot]cdc[dot]gov/eid/article/26/5/19-0993_article (Note the "wwwnc" -- which is correct. It is not "www".)