Alert to citizens,
governors, mayors, presidents, prime ministers, and public
health officials -
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.
