The Face Shield Strategy: Moving to the Community



REUTERS/Athit Perawongmetha


With the assistance of a great supply management team, we have been able to outfit all of our clinical staff with face shields. See here for our rationale and implementation. Acceptance by healthcare workers has been good and compliance is easy to visually monitor. Our message is that the shields are to be worn at all times except when eating or when in a room alone. Shields alone are worn for non-COVID care. For the care of COVID patients, masks are added beneath the shield, except in the instance of aerosol-generating procedures, when N95 respirators are worn beneath the shield. 

This week CDC recommended the use of cloth masks for all persons in public settings. Although cloth masks are better than nothing, depending on the material, the filtration efficiency varies, and they can become contaminated. Moreover, adjusting the mask increases the frequency of touching the face, which can lead to autoinoculation if the hands are contaminated. We're not very excited about this strategy. However, we believe that face shields offer a better solution for the public. Dan and I laid out the case for this in an OpEd in the Des Moines Register this week. 

The advantages of face shields are their durability allowing them to be worn an indefinite number of times, the ability to easily clean them after use, their comfort, and they prevent the wearer from touching their face. Importantly, they cover all the portals of entry for this virus--the eyes, the nose, and the mouth. Moreover, the supply chain is significantly more diversified than that of face masks, so availability is much greater. Large companies, such as Apple, Nike and John Deere, have converted production lines to make face shields. Smaller companies, such as Upstaging, have as well. Upstaging is selling shields to consumers as well as hospitals. (I ordered some from them and received them in less than 24 hours.) Because the design of face shields is simple, massive production should not be difficult. Individuals and groups are making them via 3-D printing, and they can even be made from materials that are readily available from stores that sell office or craft supplies. Our goal should be to have a face shield for every person in the country. It should be worn anytime a person leaves their home, while in any public place, and even at work. From news reports, it appears that face shields are already being more commonly worn in other nations, particularly in some Asian countries. 

Some argue that face shields may not prevent infectious aerosols that could be propelled around the edge of the shield. However, it appears that with this virus, transmission occurs mostly via droplets that do not have the ability to move in air currents and waft around the shield edges. But importantly, if everyone is shielded, these aerosols would need to move around the shield of the infected person and then waft around the shield of the uninfected person for infectious droplet nuceli to land on their face. The probability of this happening seems low, particularly since persons who are symptomatic and coughing should not be leaving their homes anyway. And hand hygiene still needs to be stressed to prevent autoinoculation. 

Some are critical of any strategy that isn't perfect. But let's think about the influenza vaccine. Although the effectiveness varies from year to year, on average it's 40%. We push this vaccine hard in the hospital and in the community. Could we expect that face shields are at least 40% effective in reducing the transmission of COVID-19? I think so. Universal shielding would bend the curve more quickly and accelerate the ability to reduce social distancing and restrictions on movement. 

Face shields are a simple solution that if implemented universally would have a major impact on public health. Until we have a vaccine, this may be our best intervention for preventing transmission in the community.


Addendum:  See our viewpoint on this topic in JAMA here.

Comments

  1. I don't appear to be in a community with rapid uptake of face shields, perhaps working a few hundred yards from CDC is partly to explain why? I am considering your arguments, and keep trying to consider how face shields could help what I believe is a failure of universal masking in nursing homes, or potentially a solution in assisted living. Performing active monitoring among nursing home residents have identified a handful of infected residents and 2 asymptomatic roommates over 10 days after one episode of HCP-->resident transmission. A prevalence sweep of testing after another identified 6 asymptomatic residents. With new admissions on hold, the importation of a single transmission can wreak havoc. Can face shields on non-COVID/PUI locations in nursing homes correct this failure of universal masking? Without trained infection control staff (which are unavailable) visiting nursing homes to provide real-time feedback on mask compliance and hand hygiene on non-COVID locations - I think it may be worth looking for a technology-based solution now.

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    1. I think it's very difficult to do universal masking given the shortage of masks in the US. I would bet that alot of nursing homes don't have the inventory to do that. I work in a major academic medical center, and we don't have the inventory to do that. Morevoer, what is the effectivness of a mask that is worn all day (or even longer). And are they wearing eye protection? Face shields solve those problems. Still need good hygiene, though.

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    2. We have universal masking through reuse and utilizing industrial N95 masks as "facemask equivalents". We will soon have the capability for universal face shields. I do like this more as there is an increase demand for N95s among various groups as the labeling of "AGP" expands.

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    3. Thank you for your excellent article. I also like the idea of the face shield. I've been making simple disposable face shields using the rubber foam, binding cover and elastic bands.

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  2. "Social Precluding via Broadly Using Simple Face Shields by the General Public"

    BRIEF:

    "Social Precluding (Social Barricading)", via broadly using the appropriate ordinary face shields (even homemade) by the general public, can have a determining role in helping to preclude the severe infection and sepsis by New Coronavirus. It can also be useful in making a balance between the Economy and Health.

    The face shield is a handy, washable, and economical tool. Everyone could find the instructions showing how to make a simple shield, via searching the Web.

    Obviously, it does not mean ignoring other necessary recommendations, like hand-washing, etc. (Having a shield precludes touching the face, too.)

    Emphasis on social precluding does not mean ignoring the benefits of "Social Distancing". Social precluding can compensate for many possible defects of social distancing. If they could be applied together with each other through an integrative attitude, it could be ideal. However, whether social distancing is appropriately applied in practice or not, social precluding can be and must be applied in any case.

    The effectiveness of the appropriate face shields in precluding the infection has been proved, but urgently conducting more studies, also including the laboratory investigations, to provide as many documents as possible is highly recommended.

    Thanks for your attention.

    K. E. (MD)

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