Unmasking Truth

Evey Hammond: Who are you?
V: Who? Who is but the form following the function of what, and what I am is a man in a mask.
Evey Hammond: Well, I can see that.
V: Of course you can. I'm not questioning your powers of observation. I'm merely remarking upon the paradox of asking a masked man who he is.
Evey Hammond: Oh, right.
--V for Vendetta

In a timely follow-up to our question of whether masks work as a COVID-19 deterrent, an MD presents a case for not wearing them based on past medical research. He observes that no scientific study has been done that conclusively demonstrates a significant deterrent effect of cloth or N95 masks on the transmission of the COVID-19 virus. Thus, any recommendations for mask wearing that claim to be 'scientifically based' must draw from research that investigates the effect of masks on transmission of reasonably similar viruses, such as the influenza virus. Fortunately, previous studies of mask:influenza transmission effects have been done and are available for scrutiny.

He focuses on a 2012 meta-study (i.e., aggregate analysis of multiple previously reported studies) published in Respiratory Viruses that found no conclusive relationship between mask use and protection from influenza. Findings from meta-analyses tend to carry extra weight because they are drawn from various studies in the past, usually over varied conditions, thus serving to increase generalizability.

As an aside, and by way of Alex Berenson, a more recent paper from Emerging Infectious Diseases, a peer reviewed journal published by, quite ironically, CDC, reports similar findings. The article, posted on the CDC site just before the COVID pandemic hit in February, presents findings from another meta-analysis of previous research on mask:influenza transmission research. The researchers "did not find evidence that surgical-type face masks are effective in reducing laboratory-confirmed influenza, either when worn by infected persons (source control) or by persons in the general community to reduce their susceptibility."

Key results are displayed in Figure 2 (below) showing statistical confidence intervals that bracket ranges of measured outcomes relative to a 'no effect' centerline for 10 previous studies of mask:influenza transmission. Those 10 studies are grouped three different ways (A,B.C) to account for some investigations that evaluated masks along side other measures (e.g., wearing masks and gloves). Because the confidence intervals do not break to the left (positive mask effect) or to the right (negative mask effect) of the 'no effect' centerline in nearly all cases, we are left to conclude that masks appear to have no significant bearing on virus transmission across a range of conditions in previous research studies.

Picking back up with the MD's stream of thought, he notes that, until recently, CDC did not recommend wearing a face mask unless a person was infected. Such a recommendation would have been wholly consistent with the research. Instead, CDC has reversed course and now recommends masks--despite no scientific evidence that demonstrates the efficacy of wearing face masks for prevention purposes.

After establishing that masks do not appear to help, the MD goes further. He argues that wearing masks might pose significant health threats. The filtering mechanism of a mask creates problems on the inbound (inhaling) and outbound (exhaling) side of breathing through the mask.

On the inbound side, the mask filter makes it harder to breathe in normal volumes of air, thus impairing respiration. This can lead to various problems, from headaches and increased airway resistance, to reduction in blood oxygenation (hypoxia) and increased blood CO2 (hypercapnia), and all the way to serious life-threatening complications. He cites several studies, some measuring the more pedestrian effects of health care workers who wear masks frequently on the job, to support his arguments.

The MD discusses several serious medical complications that might result from wearing masks for prolonged periods of time, including:

• Impairment of immunity due to low blood oxygen levels, setting the stage for contracting any infection, including COVID-19, and making the consequences of infection worse.
• Severe worsening of lung function among elderly who are frail or who have lung diseases such as COPD--as well as among lung cancer patients and those who have had lung surgery.
• Increasing spread of cancer from prolonged hypoxia--because cancer spreads best in low oxygen microenvironments.
• Increased risk of heart attacks and strokes--because hypoxia has also been proposed as a factor in the onset of atherosclerosis.

On the outbound side of breathing, masks are problematic because pathogens that the body is trying to reject through exhalation get caught up in the mesh filter. By wearing a mask, people infected with a respiratory virus are likely to exhale virus into the mask, where some of it remains and is available to be reintroduced into the respiratory system on subsequent inhalations. When they rebreathe the virus stuck in the mask filter, people wearing masks might raise concentrations of the virus in their lungs and nasal passages with potentially deadly effects.

The thrust of the MD's message is easily grasped. Currently, there is more 'science' to support not wearing masks during the present pandemic than there is to support wearing them. If you plan to heed the advice of so-called experts to wear masks, then make sure you have considered the possible risks so that you have made a more informed decision.