We have just surpassed the 100,000 death mark for COVID-19 in the United States amidst projections of a resurgence in the fall, and the wearing of a basic face mask or cloth face covering in the community is now considered a necessary non-pharmaceutical intervention (in conjunction with other protective measures) for prevention and control.
This emphasis on mask-wearing is in stark contrast to earlier advice against it. That change was prompted by the highly contagious and virulent nature of SARS-CoV-2, along with mounting evidence of asymptomatic and presymptomatic spread. The CDC now estimates that about 35% of COVID-19 infections are asymptomatic, and 40% of transmission is occurring prior to symptom onset. Nonetheless, public compliance with mask-wearing remains a challenge, and this could be attributed, in part, to misguided messaging about the benefits of face masks or cloth face coverings.
This messaging emphasizes that you wear a mask “to protect others from you, not you from others.” I believe this is counterintuitive and counterproductive. Although the scientific evidence in support of the potential protective value of mask-wearing to the wearer is sparse and of varying quality, it can be considered meaningful, nonetheless. A few experimental studies (not specific to COVID-19) have suggested that face masks may help to protect the wearer from acquiring various infections or transmitting infection. Additional support for the protective value of a face mask to the wearer can be inferred from an experimental animal study involving healthy and COVID-19-infected hamsters in separate cages, with a surgical mask used as a partition between them and serving as a proxy for the hamsters “wearing” a mask or not. This experiment documented significant protection for the uninfected animals.
Unfortunately, the message that masks have no benefit for the wearer detracts from the perceived benefit, which is a salient and statistically significant determinant of preventive health behavior, and thus this messaging undermines public health efforts to stem the pandemic.
Indeed, population control of COVID-19 requires a collectivist mindset, consistent with the public health adage “a case anywhere is a risk everywhere,” but this is easier said than done, especially in societies (including the U.S.) that are often characterized as individualistic; that is, geared toward self-protection rather than the common good. Mask-wearing has been characterized as a “culturally-determined disposition” intended as a “form of social etiquette representing courtesy to others when one is feeling sick.”
Best practice in public health aims for evidence from true experiments or randomized controlled trials, but such information is lacking for mask-wearing and COVID-19; however, triangulation of the available evidence can provide a reasonable guide for decision-making in this regard. The totality of the evidence addressed herein signals a potential protective value of a face mask or cloth face covering to the wearer against respiratory droplets, and this information should be included in messages about mask-wearing in the context of COVID-19 to facilitate more informed individual cost-benefit analysis toward the adoption and maintenance of this protective measure. In the words of FDA Commissioner Stephen Hahn, MD, “social distancing, hand washing, and wearing masks protect us all.”
Rossi A. Hassad, PhD, MPH, is an epidemiologist and professor at Mercy College, in Dobbs Ferry, New York. He is a member of the American College of Epidemiology and a fellow and chartered statistician of Britain’s Royal Statistical Society.
Last Updated May 29, 2020
Source: MedicalNewsToday.com
