COVID-19 Surveillance Testing of Healthcare Personnel Drives Universal Masking Practice

Health care professionals (HCP) are at increased risk of COVID-19 infection due to the unpredictable clinical presentation of COVID-19 disease, limited SARS-CoV-2 testing, personal protective equipment (PPE) shortages, and the inherent inability to distance from patients. Infected HCP may infect others, including coworkers, leading to a simultaneous increase in the number of infections and decrease in the availability of HCP in a community.[1] Due to PPE shortages, many healthcare systems have faced difficult decisions regarding utilization of PPE to protect HCP, patients, and the communities they serve. We describe Norton Healthcare’s success utilizing surveillance COVID-19 testing of HCP to inform the decision to increase the use of PPE during a PPE shortage in the form of universal masking. Many healthcare systems could benefit from surveillance COVID-19 testing of HCP and universal masking of HCP.


Introduction
The COVID-19 pandemic has been challenging to contain across the world due to difficulty in clinically identifying contagious individuals, lack of access to testing, and the supply of personal protective equipment (PPE). COVID-19 disease varies in its clinical presentation ranging from asymptomatic carriers to severe illness. The mechanism of transmission is not well understood, and the duration of viral shedding can be long relative to other viruses. This lead to transmission occurring in many communities long before the first cases were identified. [2] Testing for COVID-19 is cumbersome due to the reliance on nasopharyngeal swabs, suboptimal sensitivity with frequent false negative results [3], and is unreliable in access, quantity, and turnaround time in many communities. Hospitals were not uniformly stocked with sufficient PPE to meet the demands. This combination of factors potentiates the risk of COVID-19 spread in hospitals due to the inherent close contact required to provide inpatient care. PPE reduces the risk of COVID-19 transmission in hospitals, but limited supplies leads to difficult decisions for healthcare systems to determine how best to protect HCP and patients. The objective of this paper is to de-scribe Norton Healthcare's use of COVID-19 testing to inform a PPE utilization strategy of universal masking during a pandemic with limited PPE.

Intervention
Norton Healthcare is a five (four adult, one pediatric) hospital, 1,800+ licensed bed, community health system located in Louisville, Kentucky. The metropolitan area's first PCR test confirmed COVID-19 case was identified in our system on March 8, 2020. This first case did not demographically match risk factors outlined by the CDC as someone at high risk for COVID-19. Therefore, Norton Healthcare leadership assumed there had been community transmission of COVID-19 prior to March 8 that could have already affected HCP and patients. Our approach to identifying suspected inpatient COVID-19 cases was adjusted from applying CDC screening criteria to asking providers to initiate COVID-19 isolation and testing on any inpatient suspected to have COVID-19 infection without having to meet any pre-defined risk factors. By March 21, a suspected COVID-19 clinical case assessment team comprised of our antimicrobial stewardship clinical phar- macists, a radiologist, and an infectious diseases specialist were reviewing each suspected case and tracking the number of COVID-19 suspects in each adult hospital daily (Figure 1). Meanwhile, the infection prevention department was performing contact tracing of exposed employees as new cases were identified and the employee health department was fielding calls from ill employees.
Each morning, a representative from the suspected COVID-19 case assessment team met with representatives from the infection prevention and employee health teams to discuss evolving trends across the health system. As illustrated by Figure 1, hospital A was quickly identified as an outlier in number of suspected COVID-19 cases relative to the other hospitals and anecdotally had more exposed HCP per contact tracing and ill employees calling employee health. Therefore, on the morning of March 26, the decision was made to offer surveillance PCR testing to asymptomatic HCP at hospital A on a volunteer basis.
One-hundred-one employees of varying job duties volunteered to be tested by nasopharyngeal/oropharyngeal swab for COVID-19 PCR. By March 29, results showed eleven of the 101 employees (10.9%) had tested positive. Employees who tested positive were furloughed until cleared by employee health to return to work. Data regarding the number of HCP identified as exposures in known contact tracings are not available at the time of this publication. Based on this information, a universal healthcare working masking practice (Figure 2-Appendix) was implemented on March 30. Hospitals B, C, and D continued the baseline trend in suspected COVID-19 cases while the number of suspected COVID-19 cases at hospital A declined after the policy change on March 30.

Discussion
Most metropolitan areas in the United States and worldwide have struggled during the COVID-19 pandemic to adjudicate limited PPE and testing resources between hospitalized patients, healthcare workers, and members of the community. Norton Healthcare had the benefit of greater testing capacity earlier than most health care systems and was able to utilize these tests to inform the difficult decision to increase PPE utilization in our successful effort to "bend the curve" of suspected COVID-19 cases at one of our hospitals. The decision to implement a universal masking practice was challenging. While asymptomatic and presymptomatic transmission of SARS-CoV-2 has been described, there must be a balance between use of PPE now and the risk of inadequate PPE later as supply chain is not guaranteed. [4] In this case, employee testing allowed Norton Healthcare to make the decision to implement a universal masking practice based on data. The universal masking practice of HCP was effective and has since been recommended by the CDC as of April 13, 2020. [5] Transmission control of a pandemic respiratory virus requires interventions at both the community and institution level. At the community level, there were many strategies implemented by the Kentucky Governor including closing public schools on March 16, ordering all elective surgeries to cease on March 18, and all nonessential retail business to close on March 23. In addition to the universal masking practice, Norton Healthcare carried out other local interventions including visitation policy limiting visitors on March 21 (Figure 3-Appendix). All businesses, including healthcare organizations, should develop local interventions to mitigate SARS-CoV-2 transmission. Waiting on guidance from national organizations can put healthcare systems behind. During a pandemic, a period of a week could be the difference between normal operations and running out of ventilators.
In conclusions, the authors suggest that whenever possible, universal masking of HCP should be the policy of all acute and long-term care facilities during the COVID-19 pandemic. In addition, surveillance COVID-19 testing of HCP should be prioritized in hospitals and nursing homes facilities despite limited testing capacity.