Frontline Worker Safety in the Age of COVID-19: A Global Perspective : Journal of Patient Safety

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Frontline Worker Safety in the Age of COVID-19: A Global Perspective

Kavanagh, Kevin T. MD, MS*; Maiwald, Matthias MD†‡§; Pontus, Christine MS, RN, COHN-S/CCM; Cimiotti, Jeannie P. RN, PhD; Palmieri, Patrick A. DHSc, EdS, MBA, MSN, PGDip(Oxon), ACNP, RN, FFNMRCSI, FAAN#; Cormier, Lindsay E. PhD, MPH**

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Journal of Patient Safety ():10.1097/PTS.0000000000001132, May 9, 2023. | DOI: 10.1097/PTS.0000000000001132
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Conference Report

On September 14, 2022, experts from across the world came together in the form of a webinar conference to share knowledge on promoting frontline worker safety in the age of COVID-19 (Table 1).1 COVID-19 has had a profound impact on worker safety. The Brookings Institute estimates that up to 4 million workers or 2% of the U.S. workforce are not working because of long COVID.2 According to the U.S. Bureau of Labor Statistics, in the United States, there was almost a 4000% increase in workplace illness in 2020 compared with 2019, with the highest in healthcare.3 Nursing care has been especially negatively impacted during the pandemic. The median tenure for nurses working 12-hour shifts in March 2022 was 2.78 years, decreased 19.5% from the previous year. The number of new nurses within the last year filling 12 hour shifts rose by 55%.4

TABLE 1 - Faculty and Presentations, Frontline Worker Safety in the Age of COVID-19: A Global Perspective, September 14, 2022
Name of Expert Main Affiliation* Presentation Topic
Matthias Maiwald, MD Associate Professor and Senior Consultant in Microbiology, KK Women’s and Children’s Hospital, Singapore COVID-19: Singapore update
Imogen Mitchell, MBBS, PhD Professor and Executive Director, Research and Academic Partnerships, Intensive Care Specialist, Canberra Health Services, Australia Australia’s experience of COVID-19 workplace safety
Lidia Morawska, PhD, MSc Professor, Queensland University of Technology, Australia; University of Surrey, UK Airborne infection transmission and impact on frontline workers
Nele Brusselaers, MD, PhD Professor, Global Health Institute, Antwerp University, Belgium Centre for Translational Microbiome Research, Karolinska Institutet, Sweden Evaluation of science advice during the COVID-19 pandemic in Sweden
Laith Abu-Raddad, PhD Professor of Population Health Sciences at Weill Cornell Medicine-Qatar; Infectious Disease Epidemiology Group, WHO Collaborating Center for Disease Epidemiology Analytics on HIV/AIDS, Sexually Transmitted Infections, and Viral Hepatitis; Doha, Qatar. Immune protection of COVID-19 vaccination and natural infection
Eike Steinmann, PhD Professor, Department for Molecular and Medical Virology, Ruhr-University Bochum, Germany Transmission and inactivation of SARS-CoV-2
Joycelyn Elders, MD Past Surgeon General, United States Public health key to stopping infectious disease
Frazier Beatty, PhD, MPH Program Director, Master of Public Health, School of Health Sciences, Regis College, Weston, MA, United States Impact of healthcare disparities on the frontline
Ziyad Al-Aly, MD Chief, Research and Development Service, VA Saint Louis Health Care System, United States An overview of long COVID
Mengyi "Zed" Zha, MD Underserved Dermatology Fellow, University Health Systems, San Antonio, TX, United States Workplace violence against healthcare workers
Deborah Birx, MD Ambassador Deborah Birx, MD, Senior Fellow Bush Institute, United States COVID-19 USA—lessons and new tools to improve workplace safety
Jeannie Cimiotti, RN, PhD Nell Hodgson Woodruff School of Nursing, Emory University, United States Panel discussion: “the normalization of workarounds in health care: an ongoing American crisis”
Chris Pontus, MS, RN Associate Director of the Division of Health and Safety, Massachusetts Nurses Association, United States
Betty Sparks, RN, CNOR, ADN Board of Directors, Massachusetts Nurses Association, United States
Janet Hass, PhD, RN Principal Consulting Epidemiologist at Innovative Infection Prevention, New York City Metropolitan Area, United States
New York City Metropolitan Area, United States
Omid Razmpour, BSN, RN, PHN Nell Hodgson Woodruff School of Nursing, Emory University, United States
Kevin Kavanagh, MD, MS Chairman, Health Watch USA, Kentucky, United States Conference introduction and closing remarks
*Full affiliations, speaker biographical sketches and further details are available on the conference Web site at:

Researchers reported in the Lancet online survey responses from 3762 suspected and confirmed cases of long COVID; 45.2% of patients reported requiring a reduced work schedule compared with preillness. An additional 22.3% were not currently working because of illness. There was no difference between suspected and confirmed cases regarding dropping out of the workforce.5

Among the industrialized nations, the United States has not implemented a reliable, accurate, and transparent case reporting system. Similarly, the U.S. healthcare system does not have a mechanism to accurately track healthcare worker deaths.6 Kaiser Health News and the Guardian in April 2020 reported that 3607 healthcare workers have died of COVID-19,7 but as of September 2, 2022, the Centers for Disease Control and Prevention only listed 2307 healthcare worker deaths.8 There is no mandatory reporting in the United States, and what reports are received are often incomplete and inconsistent across states.

The United States, as a whole, has become numb to the devastation and deaths resulting from COVID-19. There are deaths occurring every day, which exceed the crashing of 2 large aircraft, but there has been a muted and incomplete governmental response, with relatively little public support for the utilization of effective public health interventions.9

However, several countries in Asia Pacific have continued to take the pandemic seriously. For example, Australia progressively increased masking requirements as the knowledge regarding SARS-CoV-2 spread increased. Initially, N95 masks, or respirators, were only used with procedures likely to produce aerosols. In August 2020, the State of Victoria reported that 73% of cases in nursing home workers and 54% of cases in nurses were healthcare-acquired COVID-19 infections.10 It was also noted that the chances of catching SARS-CoV-2 in the high transmission risk ICU setting, where N95 masks were worn, were lower than other settings. As evidence mounted and viral infectivity increased, there was increased awareness that wearing N95 masks was of critical importance. In Canberra, Australia, at the height of the pandemic, N95 masks plus face shields were recommended facility-wide for all frontline workers. During the height of the pandemic, Canberra also restricted its borders to other states, only reopening them when 98% of the eligible population was vaccinated.

Natural and Vaccine Immunity

No one can predict the future of a community’s immunological protection to COVID-19. Dr Abu-Raddad,11 and Dr Deborah Birx9 stressed the important differences between communities, states, and countries in the variables of age, vaccination rates, and prior exposure to variants.

In Qatar, more than 90% of the population is less than 50 years of age and the country was exposed to a large Beta surge. In this country, Dr Abu-Raddad presented data that showed immunity elicited by infection was greater than that elicited from vaccination and could last up to 3 years.

Then, the Omicron variant hit Qatar. The effectiveness against symptomatic infection for natural immunity dropped to 38% at 1 year and a 2-dose mRNA vaccine provided virtually no protection greater than 6 months after the second dose, but a 3-dose vaccine was superior to natural immunity, and by far, hybrid immunity (three dose vaccine plus previous infection) was best with an effectiveness of 77.3%.12

The United States experienced a large Omicron surge resulting in more deaths than the Delta variant. However, the U.S. population is much older, with 36% of the population above the age of 50 years.13 As one ages, immunity wanes faster.9 However, most importantly, the United States did not have a Beta variant wave.14 The Beta variant elicited cross immunity to the Omicron variant,14,15 but the Ancestral and Delta variants offered lower protection to Omicron.16

Dr Deborah Birx also presented epidemiological data, which showed continuing surges caused immunological escape variants, predicted by the excellent testing and viral sequencing in South Africa, a country with an extensive history of COVID-19 infections. Dr Birx concluded that “Natural COVID19 infection does not induce long lived immunity against reinfection” and “there is no durable herd immunity induced by natural infection with SARS-CoV-2 or its variants.”9

It is of utmost importance, as new immune escape variants emerge, that we maintain our immunity at the highest possible level. Vaccination and additional dose rates vary widely between countries, with the United States having some of the lowest among both developed and undeveloped nations. The United States also has an aging population with one of the highest rates of obesity in the world, both risk factors contributing to the U.S. high rate of COVID-19 deaths (Table 2). Qatar and Singapore have low rates of COVID-19 deaths associated with high rates of vaccination. In addition, Qatar also has a young population and Singapore has low rates of obesity.

TABLE 2 - Vaccination Status and SARS-CoV-2 Infections, Obesity, and Deaths in Nations Represented at the Health Watch USAsm Webinar
Australia Germany Qatar Singapore Sweden United States
Total cases per 1 million population 395,074 416,732 166,018 346,547 254,607 295,619
Rate of death per 1 million population 595 1,807 244 279 2,004 3,261
Population fully vaccinated 86% 76% >99% 90% 74% 68%
Additional vaccine dose 56% 74% 67% 78% 71% 34%
Population older than 65 y 15.88% 22.99% 1.19% 10.89% 20.59% 16.85%
Obesity in adult population* 30.4% 25.7% 33.9% 6.6% 22.1% 37.3%
Data Sources: Worldometer, Coronavirus; Wikipedia, List of Countries by Age Structure; New York Times, Tracking Coronavirus Vaccinations Around the World; Our World in Data, Obesity. Data as of October 24, 2022.
*Obesity in adult population 18 years and older; defined as body mass index greater than or equal to 30 (data for year 2016).


Early in the pandemic a milestone in medicine was reached. A patient-lead research team documented persistent symptoms after even mild COVID-19 infections and coined the term “long COVID” and inflicted patients were referred to as “long haulers.”17,18 In addition, with that observation, it has become apparent that the metric we need to be concerned about is the avoidance of infection. All too often, when a patient leaves the hospital, they have not recovered but merely survived COVID-19. This is also all too common even for infections considered “mild,” as potential post infection sequelae are unrecognized.

In the United States, there are estimated to be 5 to 15 million cases of long COVID and the risk of development increases with each reinfection.9 As many as 4 million workers are currently not working because of long COVID and long COVID is significantly increasing the incidence of depression.9

In a study of Veterans Health Administration outpatients, Dr Ziyad Al-Aly estimated the incidence of long COVID to be between 4% and 7%. The magnitude of risk is higher with severe disease, but it is also occurring even in those who do not require hospitalization. Several other studies have reported a higher incidence, depending on the definition used for long COVID and the population studied. For example, a controlled study from the Netherlands found that 12% of patients developed long COVID19 but did not study symptoms of cognition such as memory loss and brain fog.20 In another recent study from the City University of New York, researchers found as many as 21% of COVID-19 survivors had persistent symptoms 4 weeks or more after their acute infection.21 The United Kingdom’s census data found 45% of patients who self-reported long COVID had their acute infection at least 1 year previously.22 Long COVID can affect almost any organ of the body, up to 70% complain of brain fog and problems with cognition.20,23 Other organ systems commonly affected are the heart,24 kidney,25 and endocrine26 with an increase incidence of diabetes. The exact cause of long COVID is not known. Possibilities include permanent tissue damage, autoimmunity, viral reservoirs, and detrimental changes in a patient’s microbiome.18

Long COVID means we can no longer assure public safety with strategies that primarily rely on vaccines to avoid hospitalization and death. We need to mitigate our chance of becoming infected and avoid developing even “mild” disease. The United States will face a second wave of illness from COVID-19, one of protracted disability and reduced life expectancy. In nonhospitalized patients, COVID-19 has been associated with 8.39 excess deaths per 1000 patients, almost equaling the death rate caused acutely by severe disease.23 Dr Deborah Birx emphasized that a priority is to adequately study the incidence and effects of long COVID on healthcare workers and that long COVID is a threat to the U.S. workforce.9 As stated by Dr Ziyad Al-Aly “Governments and health systems must adapt quickly and establish post-COVID care strategies.”18

Prevention of Spread

Modern epidemiology was born in 1849 when John Snow established that a cholera outbreak in England was spread by surfaces and contaminated water and not through foul smelling air or “miasma.”27 Since that time, the spread of disease by air has too often been discounted. In the beginning of the SARS-CoV-2 pandemic, there was little emphasis regarding airborne spread with the primary focus on spread by droplets, fomites, and surfaces. This focus persisted despite early case reports of transmission within choirs and restaurants as well as laboratory evidence to the contrary.

With the dangers of long COVID and immune escape variants lessening the protection against infections provided by vaccines and natural immunity, it is imperative that additional measures be enacted to control the spread of SARS-CoV-2. This is to lower the risk of airborne transmission, which numerous studies demonstrated to be the most significant mode for many respiratory infections.28,29 For this reason, we must improve indoor air quality, use of N95 masks and respirators, and focus more attention on spread by surfaces.

Spread by Infectious Respiratory Particles

Dr Lidia Morawska described a predicament that in aerosol science, aerosols are an assembly of liquid or solid particles suspended in a gaseous medium long enough to enable observation or measurement, and droplets are liquid particles.29 However, in medical science, aerosols are considered small particles and droplets are considered large particles. It is believed that infectious respiratory particles and droplets can be filtered successfully with surgical masks. However, this is a false assumption, because particle size is a continuum, and many respiratory particles (which includes droplets) are small and can aerosolize.

Infectious respiratory particles are generated by COVID-19 patients. Small particles are produced by breathing and talking, have a propensity to aerosolize, and overall carry a high concentration of SARS-CoV-2. Larger particles, produced in the mouth, have lower concentrations of SARS-CoV-2.29

It is strongly suggested that facility protocols that only require N95 masks to be used during the performance of aerosolizing procedures should consider breathing and talking as aerosolizing procedures. The National Academies of Sciences concluded that particles the size of 5 to 100 microns can aerosolize and that an important mode of spread for SARS-CoV-2 is airborne transmission.30

Improving Indoor Air Quality

For many pathogens, 5 air exchanges per hour can reduce transmission risk by 50% or more in indoor public venues.31 With air conditioning, many buildings have become nearly airtight and are deemed unhealthy.

Monitoring of indoor air quality can be performed by patrons using portable CO2 monitors. The American Society of Heating, Refrigerating, and Air-Conditioning Engineers recommends a steady-state indoor CO2 concentration of approximately 870 ppm.32 A study from Harvard University found large differences in cognition when CO2 levels increased from 550 to 1400 ppm.33

In hospital settings, attention to airflow and quality is of utmost importance in preventing the spread of disease. In Australia, COVID-19 patients are placed in negative pressure rooms, and when these rooms are unavailable, portable air purifiers and medihoods are used. With the infectivity of new variants exceeding that of measles, the most infectious pathogen known to mankind, the required ventilation rates to mitigate the spread of SARS-CoV-2 are higher than current standards for centralized HVAC systems.34,35 Germicidal UV-C lighting is required to obtain a high-enough rate of equivalent complete air exchanges to prevent spread. Upper room UV-C lighting is based on old technology.36 It is inexpensive both to install and operate and has a high degree of safety established to prevent interaction with the skin and eyes.


Masking has been used for centuries to combat the spread of disease. Currently, masks are often a subject of disinformation. The history of changing guidance in the United States regarding masks has also amplified public confusion and resistance to wearing masks. However, the changing guidance was in response to mask shortages and the changing characteristics of emerging strains of the virus.

The infectivity of SARS-CoV-2 has progressively increased. Many regard the current variants as the most infectious pathogens known to mankind. The filtration and masking requirements have also risen. During the Omicron surge, Canberra, Australia, increased masking requirements and required N95 masks or respirators plus face shields for all frontline healthcare workers.10 Singapore went through different phases, with mandatory mask-wearing anywhere outside the own home since April 2020 and throughout all of 2021. Since then, requirements were eased, and at the time of the conference, mask-wearing was only mandatory for public transportation and healthcare facilities.37

A recent report from the Colton Foundation, COVID Collaborative, and The Rockefeller Foundation compared the effectiveness of different types of masks.38 A fit-tested N95 mask was found to be twice as effective as a nonfit tested N-95 mask. However, a nonfit tested N95 mask was found to be 2 1/2 times more effective than a surgical mask and 3 1/2 times more effective than a cloth mask. The infective dosage may differ between variants but the comparative effectiveness in protection would be expected to be similar.

The use of N95 masks are an integral and critical part of the successful pandemic response of Singapore and in large parts of Australia,10,37 and their continued use is supported by the work of Dr Lidia Morawska regarding aerosolization of SARS-CoV-2 and the ineffectiveness of clearing or inactivating airborne viruses in many indoor venues.

Spread by Surfaces

At the beginning of the pandemic, SARS-CoV-2 was believed to be primarily spread by large droplets or surfaces. An increase in handwashing and wiping packages was the cornerstone of the U.S. initial response. However, as data continued to accumulate, it became apparent that the major route of spread was by aerosolization. A study of an outbreak at a hospital in Hong Kong concluded that up to 63% of the transmission was by the airborne route. The authors stated “SARS-CoV was less probable to transmit via the fomite route alone.”28 In the case study, spread by fomites was estimated to be between 37% and 60%.

Both direct contact and fomite spread can occur with SARS-CoV-2. Because of the high viral transmission rate, a significant number of individuals can be infected, even if they comprise a minority of infected individuals. Dr Eike Steinmann discussed the use of antiseptics in healthcare settings, which can be used to deactivate SARS-CoV-2.39 The WHO recommended hand rub solution, which is suitable for on-site production, uses ethanol at a concentration of 80% plus hydrogen peroxide at 0.125% (v/v) or isopropanol at 75% with hydrogen peroxide at 0.125% (v/v).

Being an enveloped virus, SARS-CoV-2 is inherently unstable and easily inactivated. Dr Steinmann presented data that showed that both ethanol and isopropyl alcohol readily inactivates the virus at concentrations of 30% to 40%. In nonhospital or home settings, soap and water can also be used. Soap and water not only mechanically removes the virus, but a new study confirms that soap also deactivates the virus by disrupting its lipid-protein envelope.40

SARS-CoV-2 has been reported to be viable for up to 16 hours in aerosols.41 On surfaces, the virus seems viable on plastic and stainless steel for 2 to 3 days but only lives for approximately 4 to 8 hours on copper and cardboard, respectively. Dr Steinman reported that infectivity measured by the Touch Transfer Assay failed to demonstrate viral transmission from surfaces which have been dry for 30 minutes.42 He also presented data that suggests there is a low-risk of transmission from surfaces exposed to coughing or aerosolized particles. He concluded that SARS-CoV-2 transmission from surfaces is not a major factor in the spread of the virus.

Misinformation and Disinformation

Disinformation has been a major impediment to widespread adoption of public health strategies, including vaccinations and masking. Early in the pandemic, the European Union warned of a Russian disinformation campaign using “contradictory, confusing and malicious reports to make it harder for the EU to communicate its response to the pandemic.”43

Dr Nele Brusselaers made a compelling case regarding data integrity problems and disinformation embedded in the Swedish COVID-19 response.44 She expressed concern that other countries were using Swedish strategies as examples of success when many epidemiologists viewed them as failures. Sweden apparently failed in their strategy to achieve herd immunity. Masks were often described as dangerous and were discouraged in healthcare settings. Healthcare workers were not allowed to use masks in some facilities and one worker was even fired for wearing one. Overall, Sweden had more deaths, hospitalizations, and ICU admissions than the neighboring Nordic countries of Denmark, Norway, Iceland, and Finland.45 However, many continue to view Sweden as a success.

The failed strategy was also evident in Sweden’s schools, where all too often, the wearing of masks was discouraged or not allowed, and “The (Swedish) Public Health Agency denied or downgraded the fact that children could be infectious, develop severe disease, or drive the spread of the infection in the population; while their internal emails indicate their aim to use children to spread the infection in society.”46

Disinformation from Sweden has seemed to influence policy in other countries. During a U.S. Senate Hearing, results from Sweden were used to argue that schools should not be closed and that Sweden had excellent results stating, “I don’t think there’s anybody arguing that what happened in Sweden is an unacceptable result.”47 Many uninformed segments of the population and people unfavorable to masking continue and people unfavorable to masking continue to view Sweden’s response as a success.

However, as articulated by Dr Joycelyn Elders, getting children back to school is a priority. This needs to be done safely, by encouraging vaccinations, and providing safe ventilation, an intervention which would also decrease the transmission of other airborne illnesses and improve cognition. Finally, proactive testing and masking needs to be used in times of SARS-CoV-2 surges.

One of the biggest future concerns of Dr Deborah Birx is that COVID, Respiratory Syncytial Virus, and influenza cases may rise in children in the Fall, which will lead to community spread and rising rates of hospitalizations among vulnerable Americans.9 She also described how the seasonality of COVID-19 surges differs between different regions in the United States, making population-based protection more difficult to control community spread.

One possible strategy would be for schools to vary their schedules to avoid surges and to hold classes during the months when windows can be opened, thus increasing ventilation.

COVID-19 disinformation has also augmented violence against frontline workers, especially when parents of students or patrons decline to follow public health advice regarding masking and social distancing.

Dr Mengyi “Zed” Zha, discussed a large prepandemic meta-analysis, which found that 61% of healthcare workers reported either nonphysical (42.5%) or physical (24.4%) workplace violence.48 The most common cause was dissatisfaction with care. One can easily imagine how a family’s insistence to use disproven therapies and ineffective drugs can result in significant conflicts in the workplace.


In 2022, the United States faced a triple threat of monkeypox, polio, and SARS-CoV-2. Public health recommendations are not readily followed by the public, and elimination of these pathogens from our communities is in doubt. The conference delineated several areas, which should be improved to promote healthcare safety, and this includes expansion of testing and use of N95 masks, along with improvements in ventilation. These interventions can mitigate airborne pathogens, including seasonal influenza which patients and staff are exposed to. In addition, healthcare staff should be provided with a healthcare and economic safety net, including an established leave policy.

It is imperative that we invest in our healthcare infrastructure and abandon the cost-driven strategy of lean staffing and just-in-time supply chains. In some areas of the United States, facilities furloughed nurses during the early days of the pandemic, causing nurses to leave their community and go to New York City where they were offering salaries of $10,000 a week.49 When nurses were needed in community hospitals, few were available. This led to the employment of temporary and agency nurses who had little if any experience with the hospital’s protocols, electronic medical records system, or equipment. In some regions of our nation, on any given day, more than half of the nurses are contract nurses.49

It is of paramount importance that we engage community businesses to upgrade ventilation and install germicidal ultraviolet air disinfection, along with providing high-quality protective gear for workers. As stated by past Surgeon General Joycelyn Elders and Dr Frazier Beatty, the most effective way to motivate a community is to engage trusted community leaders who can educate and persuade their citizens to adopt public health strategies. Community leaders are also an extremely important voice in combating the rampant COVID-19 disinformation, which is hobbling our pandemic response.


The authors thank Imogen Mitchell, Joycelyn Elders, Nele Brusselaers, Eike Steinmann, Laith Abu-Raddad, Deborah Birx, Lidia Morawska, Joycelyn Elders, and Ziyad Al-Aly who reviewed and provided comments regarding final versions of the manuscript. The authors also thank Mary Crotty for her conference input and manuscript review.


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COVID-19; SARS-CoV-2; aerosolization; masks; spread; fomites; disinformation; Sweden; Australia; workplace safety; immunity; vaccination; long COVID; disparities

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