Four years ago, before our world was upended by the COVID-19 pandemic, we authored an article titled “No Boundaries: IH’s Role in Preventing the Transmission of Highly Hazardous Communicable Diseases” that was published in the April 2018 Synergist. The purpose of that article was twofold: first, to reflect on our experience working in the Nebraska Biocontainment Unit during the 2014–2016 West Africa Ebola outbreak and share best practices, and second, to illustrate how industrial hygienists are well positioned to respond to highly hazardous communicable diseases as their incidence continues to rise worldwide. We did not intend for our 2018 article to be foreboding, but rather food for thought. Then, in early 2020, the role of IHs drastically changed as they acquired new responsibilities related to infectious disease mitigation and management. With our world getting smaller each day given the ease of transporting goods and people, as well as climate change’s negative environmental impact blurring the lines between animal ecosystems and pathogen reservoirs (as described in a 2017 paper published in Environment International), another pandemic in our lifetime is a real possibility. As we know, hazards unrelated to a pandemic do not disappear during pandemic times; rather, IHs are tasked with addressing these hazards and those arising from a pandemic simultaneously. As IHs, we need to be adept at controlling everyday hazards while responding to those brought about by infectious disease outbreaks. These past two years have demonstrated that a pandemic drastically increases the IH workload and can result in additional challenges that may increase or conceal everyday hazards. For example, extra personal protective equipment worn during infectious disease mitigation tasks can both increase heat stress and conceal visual cues associated with that heat stress. So, how do we prepare for the next pandemic when we have not yet recovered from nor understood the full, long-term impacts of COVID-19? What lessons have we learned, and how do we ensure that we don’t become complacent as the current pandemic appears to wane? HIERARCHY OF CONTROLS LESSONS LEARNED The hierarchy of controls is an important part of the IH toolkit. Two recent AIHA publications cover controls as well as planning, assessment, control banding, and other applicable considerations in infectious disease mitigation and management: Essentials of Pandemic Response: Considerations for Controlling COVID-19 and Other Infectious Diseases and the second edition of The Role of the Industrial Hygienist in a Pandemic. The following hierarchy-related takeaways may be relevant to the next epidemic or pandemic. Elimination. Early in the COVID-19 pandemic, each state responded differently—some by issuing no stay-at-home orders and others by issuing orders that lasted weeks for nonessential services in March and April of 2020. However, compared to other nations such as New Zealand and Taiwan, the United States’ effort to contain the virus through “lockdown” was minimal and only served to slow the inevitable unmitigated community spread. Quarantine and isolation will continue to be useful elimination measures and should be enforced when appropriate and possible. Substitution. Cleaning and disinfection are routinely employed against any microbial agent, but overapplication or improper combinations of chemicals can sometimes cause adverse human health effects. Substitution for less hazardous chemicals or less hazardous application techniques can reduce the overall negative human health impact while effectively decreasing the microbial dose. EPA and other credible sources widely publish disinfectant lists for known pathogens of interest, including EPA’s List N for COVID-19. Engineering controls. Heating, ventilation, and air conditioning (HVAC) adjustments have been shown to be effective engineering controls against airborne and aerosol transmissible diseases, including COVID-19. Actions such as increasing the number of air changes per hour allow for the quicker removal of viral particles from the air, and increasing filter efficiency while reducing HVAC air recirculation dilutes particles. (See the Essentials of Pandemic Response and The Role of the Industrial Hygienist in a Pandemic publications for additional information in this area.) Administrative controls. The pandemic has demonstrated that life indeed goes on without everyone in the office. Some studies have found increased job satisfaction due to remote work options (for a couple of examples, see the papers in the International Journal of Trade & Commerce-IIARTC and Sustainability in the “Resources” section below). To boost worker satisfaction and decrease the likelihood of turnover or resignation, these flexible work arrangements should continue fully or partially, with telecommuting schedules coordinated between employers and employees. Employers must also contend with the difficult task of addressing workers’ ergonomic needs in telecommuting environments. Personal protective equipment. The pandemic ushered in the widespread use of cloth face coverings, surgical masks, KN95s, NIOSH-approved filtering facepiece respirators, and other FFRs. Most people are now at least aware of different types of respiratory protection, but education is needed to teach the general public to utilize masks properly and within their limitations. Workplaces both with and without employees in mandatory respiratory protection programs have likely seen the formation of bad habits that calcified during the pandemic. For instance, some workers may not be wearing the correct fit-tested models. Skipped seal checks as well as improper storage and management of respiratory protection (for example, workers shoving respirators into their pockets between uses) are additional examples. Lax respiratory protection habits like these will require refresher training with hands-on skills practice to remediate these issues. COMMUNICATION Communication became a major problem for all parties—from federal agencies to employers—during the COVID-19 pandemic and will remain a struggle in any future pandemic. Intentional and unintentional misinformation is rampant, with social media facilitating the spread of this secondary pandemic of misinformation, as described in the journal JMIR Public Health and Surveillance. Throughout the COVID-19 pandemic, decisions have had to be made without complete information (particularly early on, for example, when researchers were still collecting data on the virus’s incubation period, modes of transmission, and infectious dose). Fortunately, IHs are problem solvers, skillful at extrapolating current knowledge and past experiences to provide direction when there is a dearth of reliable information and adjusting course when new information becomes available. However, we must ensure that the stakeholders and lay populations we work with understand that with an emerging pathogen comes evolving breakthroughs in knowledge and understanding, so we expect the information to change. Communication needs to be clear and transparent.

AURORA LE, PhD, MPH, CSP, CPH, is the John G. Searle assistant professor of environmental health sciences at the University of Michigan School of Public Health. She served as a research assistant for the Nebraska Biocontainment Unit in 2015–2016 and assisted the Office of the Assistant Secretary for Preparedness and Response in developing a training curriculum on the management of highly infectious remains.

SHAWN GIBBS, PhD, MBA, CIH, is dean of the School of Public Health at Texas A&M University and professor of environmental and occupational health. He served as the director of research for the Nebraska Biocontainment Unit in 2009–2015. He also assisted CDC and the Office of the Assistant Secretary for Preparedness and Response in crafting guidelines on Ebola patient transport, decontamination, and handling of highly infectious remains.