Emporia Gazette, By John Richard Schrock Emporia
If you believe the earth is flat, you will eagerly embrace “The Travel Mask Mandate Repeal Act of 2021” led by Senator Rand Paul (KY) and cosponsored by Senators Marshall (KS), Mike Braun (IN), Tom Cotton (AR), and Roger Wicker (MS). Senator Marshall proclaimed: “This is a time to believe in science, not anxiety or panic.... The science does not support a new mask mandate if you’ve been vaccinated or if you’ve had the virus.” They are dead wrong!
Of course the earth is not flat, and the past strong evidence for face masks providing protection has become even stronger. Just this June 25, the premier world journal Science published another peer-reviewed study “Face masks effectively limit the probability of SARS-CoV-2 transmission” authored by an international team led by researchers at the Max Planck Institute in Germany.
Fifteen graphs in this five-page article summarize the substantial data that have accumulated and detail the extent face masking limits virus transmission. The first effect or “source control” comes from an infected person wearing a mask that reduces their emission and spread of the airborne virus. The second effect is “wearer protection” that reduces the inhalation of airborne droplets and aerosols from others. The third measured effect is when both parties are wearing masks, called “universal masking.”
Data clearly show that protection is greatest when both parties are wearing a mask. But “source control alone is more effective than wearer protection alone....” They found “masks are more effective in removing larger particles, and freshly generated respiratory particles are usually largest at the source, shrinking upon evaporation in indoor air.”
Their graphs for “infection probability” confirm the crucial need to wear masks. I have previously described this as the “I wear a mask to protect you,” and “you wear a mask to protect me” principle. Since up to half of COVID-19-infected persons may not have symptoms, folks who feel healthy can still transmit the virus. That includes some vaccinated people who will not develop symptoms. Therefore, mask wearing as well as distancing remain important for protecting others.
The type of mask is important. These researchers found “that a person typically emits a total number of 3,000,000 particles during a 30-minute period.” This means that “indoor environments are usually in a respiratory particle-rich regime.” Their analysis includes a comparison of surgical masks and N95 or FFP2 masks with less than 5% particle penetration, as well as surgical and other masks that have penetration rates from 30 to 70%.
The importance of this study is its use of data and math analysis to graph the variable effectiveness of masks when the virus levels in the aerosols in the air are low, versus situations where the air is virus-rich. Their data show that “...mask efficiency strongly depends on airborne virus abundance” and that “virus abundance in most environments is sufficiently low for masks to be effective in reducing airborne transmission.”
The worrisome part of their graphs shows how protection from masks is compromised in virus-rich situations. The intensive care units for COVID-19 patients during the massive outbreaks in New York and elsewhere would be examples of virus-rich situations. Well before this data was available, healthcare workers intuitively saw this danger. Some went to hotel rooms rather than return home each night and endanger their families. This research proves they were correct. Today, many medical workers in virus-rich ICU wards are wearing hazmat suits with self-contained air supplies, and for good reason.
More research remains to be done, especially on whether the inhaled dosage affects the severity of the infection. But the effectiveness of face masking in this pandemic continues to be confirmed. No peer-reviewed science says otherwise.
But two of the five sponsors of this proposed mask mandate repeal proposal are medical doctors. One has touted abandoning a mask being a reward for becoming vaccinated. Another claims that wearing masks causes psychological damage to children and adults, again totally unsupported non-science.
http://www.emporiagazette.com/free/article_8b57b9f8-f3ac-11eb-9788-e7d923ed2911.html
