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, Moving Personal Protective Equipment into the Community, on this topic in JAMA.

What scares you?

I’m on a quick weekend trip for a wedding—a trip made possible only because we have a high concentration of hospital epidemiologists in Iowa City, and we haven’t yet diagnosed* a case of COVID-19 (*like much of the country, we’re behind in testing).

It’s disorienting to go from non-stop response planning questions to connecting with old friends. But of course the questions still came, the most common being: “are you scared by this?” My response was “yes”. Here are the three reasons I gave for my concern (before trying to turn the conversation to other things!), in no particular order:

Our healthcare system lacks surge capacity, and is already overstretched. Large tertiary care centers commonly run at capacity with overflowing emergency departments and patients “orbiting” (awaiting transfer from smaller hospitals for a higher level of care). The proportion of COVID-19 patients requiring admission and ICU-level care will quickly overwhelm US hospitals if spread continues at plausible estimated rates. This will cripple our ability to care not only for COVID-19 patients for all others requiring hospital care.

Residents of long term care facilities (LTCF, including long term acute care, rehabilitation centers, etc.) are extraordinarily vulnerable. We know from experience that once a transmissible pathogen enters a LTCF it spreads quickly, and the experience at the Life Care Center in Washington is terrifying.

The social and economic disruption caused by COVID-19 may kill more than the virus does directly—particularly in countries that have frayed or nonexistent social safety nets (I include the US in the “frayed” category). Job loss, loss of health coverage, homelessness, all carry with them additional morbidity and mortality that will continue long after the COVID-19 pandemic is over.

What do my fears imply for response planning?

Lack of surge capacity requires aggressive approaches to keep all but the sickest patients out of the hospital (telehealth, home health), and developing plans for conversion of some general hospital units to ICU-level care if needed. No surge capacity also strengthens the argument for aggressive social distancing approaches in an attempt to “flatten the curve” of the epidemic (amazingly helpful graphic below, and great Twitter thread here), while admittedly worsening the social/economic disruption problems.

The vulnerability of LTCF residents requires drastic measures to protect these facilities—limiting facility access, screening employees for URI/ILI daily, and reducing social contact in ways that could still allow interaction (computer/tablet visits, etc.). Some may even wish to investigate temporary relocation of some residents (e.g. to family with visiting nurse assistance). LTCFs look more and more like the highest risk environments for COVID-19 (combining transmissibility with case fatality rate).

The social and economic disruptions are the most difficult to address. In the near term, it requires recognizing when some of the more disruptive control strategies are no longer providing a benefit that overrides the ongoing damage to society. As one example, I think we’re reaching a point at which travel restrictions will have diminishing returns. This excellent modeling paper demonstrates the likely benefit of travel bans from China before extensive international spread had occurred. The impact of travel restrictions is likely to be much less now that the virus is so widespread globally. In fact, I think the motivation for many current travel restrictions being implemented in the US is out of fear that the traveler will be subject to home quarantine upon return (and unable to work or contribute to response efforts)—once community spread is documented across the US, the use of home quarantine after travel becomes illogical. Moreover, the whole idea of quarantining healthcare personnel after exposures needs to be abandoned if we hope to have any work force for patient care. CDC recognizes this in recent updated guidance.

OK, now that I’ve revived this recently moribund blog, we’ll have to address some more COVID-19 controversies soon. Or you could just search the site for our 10 year old posts about the H1N1 N95 mask fiasco?