Recently Pandemic Data Analysis (PANDA) has started spreading "infobites" under the heading "Facts Not Fear".  Here I address these and show how they are misrepresenting facts.  Number 7/13 addresses masks.

Claim 1

PANDA starts off by saying that:

Numerous conflicting messages about masks were issued to the public by health authorities.

I tend to agree with them here but only early in the pandemic.  Early in 2020 Fauci did not think everyone needed to wear masks but he walked that back.  He is quoted as saying:

We were not aware that 40 to 45% of people were asymptomatic, nor were we aware that a substantial proportion of people who get infected get infected from people who are without symptoms. That makes it overwhelmingly important for everyone to wear a mask.

In 2021 it should be very clear that mask wearing is useful in reducing COVID-19 transmission.

Claim 2

PANDA then says:

The CDC published a meta-analysis in May 2020 stating, “We did not find evidence that surgical-type face masks are effective in reducing laboratory-confirmed influenza transmission”.

1. This is an article in a journal (Emerging Infectious Diseases) published by the CDC.  It's not the opinion of CDC but that of the authors Xiao et al. (2020).  This confuses PANDA to no end.
2. The researchers are not even investigating COVID-19 but flu.  

Claim 3

PANDA then claims:

The WHO published Interim guidance in June 2020 stating “At present, there is no direct evidence on the effectiveness of universal masking of healthy people in the community”.

The quote is paraphrased but broadly accurate in the source.  The exact quote is this:

At present, there is no direct evidence (from studies on COVID19 and in healthy people in the community) on the effectiveness of universal masking of healthy people in the community to prevent infection with respiratory viruses, including COVID-19

What's wrong is that the quote is not the interim guidance.  The WHO guidance on masking for the healthy is this:

However, taking into account the available studies evaluating pre- and asymptomatic transmission, a growing compendium of observational evidence on the use of masks by the general public in several countries, individual values and preferences, as well as the difficulty of physical distancing in many contexts, WHO has updated its guidance to advise that to prevent COVID-19 transmission effectively in areas of community transmission, governments should encourage the general public to wear masks in specific situations and settings as part of a comprehensive approach to suppress SARS-CoV-2 transmission.

So the source quoted by PANDA actually recommends masking in areas of community transmission.  They also recommend for people with COVID-19 or those taking care of people with COVID-19.

Claim 4

PANDA quotes Dr. Fauci

The typical mask you buy in the drug store is not really effective in keeping out virus, which is small enough to pass through the material.

AP did a fact check on this that explains it.  Essentially they conclude that the quote is from February 2020 from a released email of Dr. Fauci.  So it comes from a time where very little was known.  They then show that:

In February and March 2020, Fauci advised the public against wearing masks, but later updated his position, noting masks are essential to help curb the outbreak.

So he updated his views as more data became available.

Claim 5

PANDA then claims:

The data shows mask mandates don’t reduce viral spread.

The data in this case is a single preprint paper based on observational data.  The paper appears to be published now so we refer to that.

The conclusion is:

We did not observe association between mask mandates or use and reduced COVID-19 spread in US states. COVID-19 mitigation requires further research and use of existing efficacious strategies, most notably vaccination.

This study didn't find an observed association.  It's not clear that they controlled for all confounders.  We also have several other studies that find the opposite:

Cheng et al. (2021) conclude that:

On the basis of direct measurements of SARS-CoV-2 in air samples and population-level infection probabilities, we find that the virus abundance in most environments is sufficiently low for masks to be effective in reducing airborne transmission.

Abaluck et al. (2021) (preprint) in a large randomised trial establishes:

A randomized-trial of community-level mask promotion in rural Bangladesh during COVID-19 shows that the intervention tripled mask usage and reduced symptomatic SARS-CoV-2 infections, demonstrating that promoting community mask-wearing can improve public health.

In a review Howard et. al (2021) find that:

The preponderance of evidence indicates that mask wearing reduces transmissibility per contact by reducing transmission of infected respiratory particles in both laboratory and clinical contexts.

Brooks and Butler (2021) also review the work out there an conclude:

An increasing number of ecological studies have also provided persuasive evidence that universal mandatory mask wearing policies have been associated with reductions in the number or rate of infections and deaths .

PANDA is wrong again.

You can find more in this series of posts here.