Surveillance of healthcare workers essential in early phase of pandemic

Close monitoring of healthcare workers (HCWs) early in an emerging infectious disease outbreak is necessary in determining the effectiveness of infection prevention measures that have been implemented, suggests a Singapore study.

“In the early days of an emerging infectious disease outbreak when there is little data to inform practice and anxiety is highest among HCWs, close monitoring is an important surveillance strategy to both evaluate the effectiveness of infection prevention measures and reassure HCWs,” the researchers said.

This retrospective cohort study was carried out in Singapore General Hospital (SGH), a 1,822-bed tertiary hospital, and included all HCWs working in SGH during the study period. HCW protection measures included clinical workflows and personal protective equipment that were developed and adapted to minimize the risk of SARS-CoV-2 transmission.

HCW monitoring consisted of the following: staff contact logs in high-risk locations, twice-daily temperature monitoring, assessment of HCWs with acute respiratory illnesses (ARIs) in the staff clinic, and extensive contact tracing, detailed risk assessment, and risk-based interventions in the event of exposure to SARS-CoV-2. Surveillance utilized monitoring data and ARI presentations and outcomes.

Of the 1,946 HCWs at risk of occupational COVID-19, 333 (17.1 percent) presented with ARI between 6 January 2020 and 16 March 2020, and 32 of them (9.6 percent) tested negative for SARS-CoV-2 from throat swabs, while five others (two medical social workers, a psychologist, a nurse, and a researcher) developed COVID-19 due to nonclinical exposures. [Singapore Med J 2021;doi:10.11622/smedj.2021083]

“Three were from community exposures (medical social worker, nurse, and researcher), one was imported (the psychologist returned from a conference in the US), and one was a probable transmission in the nonclinical office area of the hospital (second medical social worker),” the researchers noted.

During the same period, nine COVID-19 exposure episodes were investigated, leading to 189 HCW contacts traced. Of these, 68 (36.2 percent) were placed on quarantine and remained well.

A study in another Singapore acute care hospital in April 2020 reported that HCWs in the operative theatre and intensive care unit had high confidence in COVID-19 protection at work, which showed the effectiveness of the early measures employed. [Singapore Med J 2021doi:10.11622/smedj.2021046]

“Healthcare personnel are integral to the control of an outbreak and constitute a scarce resource that cannot be rapidly augmented,” the researchers said. “Health systems have to recognize their critical role and allocate adequate resources for their protection.”

Of note, HCW surveillance should also check reactions and performance as well as provide psychosocial support on top of monitoring data and ARI presentations. [N Engl J Med 2020;383:510-512]

“The mental health of HCWs impacts their behaviour, adherence to infection prevention measures, and response to unexpected situations during clinical care,” the researchers said. “Although psychological support has been provided to HCWs through peer support services, systematic and follow-up assessments on anxiety have not been carried out among frontline HCWs in our institution.”

Other limitations of the present study included the absence of laboratory testing in identifying asymptomatic infection, and the staff contact log was time- and resource-intensive to sustain in the longer term. Data in the staff log were also dependent on memory recall, so data entry might not be consistent or accurate.

“HCWs are a sentinel surveillance population in an emerging infectious disease outbreak,” the researchers said. “Their clinical status is a measure of the preparedness and response of the health system they work in.”