Is “Enough” Really Enough? How Protected Are Our Most Vulnerable Workers—Those That Support Our Country’s Economy and Infrastructure?

By Shelton Lo and David C. Christiani



Lo S and Christiani D. Is “enough” really enough? how protected are our most vulnerable workers—those that support our country’s economy and infrastructure? HPHR. 2021; 33.


Is “Enough” Really Enough? How Protected Are Our Most Vulnerable Workers—Those That Support Our Country’s Economy and Infrastructure?

In a congressional letter sent on March 1st, 2021 addressed to the White House COVID Response Coordinator Jeff Zients, the Centers for Disease Control and Prevention Director Rochelle Walensky, and the U.S. Department of Labor’s Acting Secretary Al Stewart,1 a group of public health leaders in the fields of infectious disease and aerosol science voiced their concerns about the current CDC recommendations on workplace aerosol exposure protection and urged OSHA to use the most recent information about PPE in their upcoming March 15 promulgation of an emergency standard.


With the recent SARS-CoV-2 plans, the availability of life-saving vaccines has expanded, the call for the widespread use of masks has increased, and stronger measures and guidelines to protect workers and the public have been implemented.2 But these measures are not enough. Vaccinations are not a viable short-term solution because new variants can develop rapidly, long before the majority of the population can receive the vaccination.3 Current regulations and recommendations on the types of masks people should wear are insufficient and are not regularly updated. SARS-CoV-2 infection rates and death rates recently reached record-high levels,4 which indicates that there is an urgent need for further action. There is still much to be done to prevent SARS-CoV-2 infections and deaths.


More importantly, infection rates have highlighted the disproportionate impacts of SARS-CoV-2 on essential workers, Blacks, Latinos, and other vulnerable high-risk groups. As stated in the congressional letter: “Throughout the pandemic, worker infections have fueled major outbreaks across the country [and] many essential workers at the greatest risk of contracting and dying from COVID-19 are people of color.”1. This indication is both important and frightening, especially for our essential workers who are risking their health in order to serve their communities. For essential workers, this is a major issue that needs to be addressed immediately. Gathering and working in indoor environments without adequate ventilation or protection from droplets and smaller aerosol particles places individuals at a particularly high risk of contracting SARS-CoV-2.5  This risk is even greater when asymptomatic and pre-symptomatic viral shedding occur.6


Unfortunately, most CDC guidelines and recommendations still have not been updated to limit exposure to potentially contaminated aerosol particles1 . Most CDC guidelines remain largely focused on preventing contact with infected individuals and exposure to droplets which, although very important, are not sufficient to protect the working population from SARS-CoV-2.1 As stated in the congressional letter, “CDC guidance continues to rely on the view—which is outmoded according to the Experts’ Letter—that most COVID-19 infections are caused by contact with larger infectious droplets.”1 The current recommendations fail to include the control measures necessary to protect workers from inhalation exposure to the coronavirus that causes SARS-CoV-2. In particular, enhanced respiratory protection is needed to better protect workers against inhalation exposure to the virus.7 A multi-faceted solution is needed, such as mandating that N95 respirators or acceptable equivalents are provided by employers in high-risk fields, requiring higher quality masks for essential workers and the general public, offering regular fitness tests and trainings, using effective alternatives to N95 masks such as loose-fitting respirators where appropriate, enhancing and updating indoor ventilation where necessary, and more strictly enforcing public health laws. It is the responsibility of employers, who are limited by CDC guidelines and recommendations, to secure sufficient supplies of rigorously tested personal protective equipment for their employees in order to adequately protect them against infectious diseases, especially for their essential workers who are placing their lives at risk in order to serve their communities.


Just like the push forward with the congressional letter, we, as public health professionals and as a community in general, need to urge for an even stronger immediate action to strengthen measures that limit our vulnerable working population’s exposure to SARS-CoV-2. The current recommendations are insufficient. Updates are urgently needed to protect those who are at greatest risk of occupational exposure to the novel coronavirus and to ensure that protective and preventive standards are consistent with the latest science and CDC guidelines that fully recognize airborne transmission as hazardous.


1. Immediate Action is Needed to Address SARS-CoV-2 Inhalation Exposure [Letter to Jeff Zients, Rochelle Walensky, Al Stewart]. (2021, February 15).


2. Soucheray, S. (2021, February 10). Feds focus on Mask upgrades, COVID-19 vaccine sites. Retrieved March 03, 2021, from


3. New study of coronavirus variants predicts virus evolving to escape current vaccines, treatments. (2021, January 28). Retrieved March 03, 2021, from


4. COVID-19 response and Recovery monthly Bulletin (February 2021). (2021, February 28). Retrieved March 03, 2021, from bruary-2021

5. Tang, S., Mao, Y., Jones, R. M., Tan, Q., Ji, J. S., Li, N., Shen, J., Lv, Y., Pan, L., Ding, P., Wang, X., Wang, Y., MacIntyre, C. R., & Shi, X. (2020). Aerosol transmission of SARS-CoV-2? Evidence, prevention and control. Environment international, 144, 106039.

6. Johansson MA, Quandelacy TM, Kada S, et al. SARS-CoV-2 Transmission From People without COVID-19 Symptoms. JAMA Netw Open. 2021;4(1):e2035057. doi:10.1001/jamanetworkopen.2020.35057

7. Petsonk, E. L., & Harber, P. (2020). Respiratory protection for health care workers: A 2020 COVID-19 perspective. American journal of industrial medicine, 63(8), 655–658.

About the Authors

Shelton Lo

Shelton Lo is a PhD student in the Population Health Sciences Program at the Harvard T.H. Chan School of Public Health, with an emphasis in Environmental Health. His research interests focus on environmental epidemiology and occupational health.

David C. Christiani

Dr. Christiani is a physician and researcher who is the Elkan Blout Professor of Environmental Genetics in the Department of Environmental Health; and Professor of Medicine at Harvard Medical School/Massachusetts General Hospital. Director of the Harvard TH Chan Education and Research Center for Occupational Health and Safety.