Containment of COVID-19 cases among healthcare workers: The role of surveillance, early detection, and outbreak management

Abstract

Objective: Staff surveillance is crucial during the containment phase of a pandemic to help reduce potential healthcare-associated transmission and sustain good staff morale. During an outbreak of SARS-COV-2 with community transmission, our institution used an integrated strategy for early detection and containment of COVID-19 cases among healthcare workers (HCWs).

Methods: Our strategy comprised 3 key components: (1) enforcing reporting of HCWs with acute respiratory illness (ARI) to our institution's staff clinic for monitoring; (2) conducting ongoing syndromic surveillance to obtain early warning of potential clusters of COVID-19; and (3) outbreak investigation and management.

Results: Over a 16-week surveillance period, we detected 14 cases of COVID-19 among HCWs with ARI symptoms. Two of the cases were linked epidemiologically and thus constituted a COVID-19 cluster with intrahospital HCW-HCW transmission; we also detected 1 family cluster and 2 clusters among HCWs who shared accommodation. No transmission to HCWs or patients was detected after containment measures were instituted. Early detection minimized the number of HCWs requiring quarantine, hence preserving continuity of service during an ongoing pandemic.

Conclusions: An integrated surveillance strategy, outbreak management, and encouraging individual responsibility were successful in early detection of clusters of COVID-19 among HCWs. With ongoing local transmission, vigilance must be maintained for intrahospital spread in nonclinical areas where social mingling of HCWs occurs. Because most individuals with COVID-19 have mild symptoms, addressing presenteeism is crucial to minimize potential staff and patient exposure.

Fig. 1.

Surveillance for acute respiratory illness among healthcare workers (HCWs) at an acute- and tertiary-care hospital during a COVID-19 epidemic, prior to the detection of a cluster of COVID-19 cases among HCWs. (A) Among HCWs, percentage of staff clinic and emergency department visits attributed to acute respiratory illness over an 11-week period. (B) Heat maps illustrate clustering of HCWs with symptoms of acute respiratory illness, clustered by duration of symptoms and by reporting location (departments), with a focus on the medical social work department over weeks 10 and 11 of the study period, prior to the detection of a staff cluster among medical social workers. The disease outbreak response system condition (DORSCON) is a color-coded framework used by our local ministry of health to indicate the severity of the current outbreak situation and to activate a series of interventions. DORSCON yellow indicates that disease is severe but is occurring outside Singapore, and DORSCON orange indicates that disease is severe, with ongoing local transmission, but it is currently being contained. Note. UCL, upper limit of confidence; LCL, lower limit of confidence.

Fig. 2.

Distribution of healthcare workers (HCWs) with significant contact history, symptomatic HCWs, and office layout, during detection of a cluster of COVID-19 cases among HCWs. (A) Main medical social services office layout. (B) Series of single-room offices used by senior medical social workers located on the same floor. (C) Off-site medical social services office located in another office tower. (D) Typical layout in main medical social services office at the time of the outbreak. ^†A total of 49 staff were placed on quarantine (home isolation) based on significant unprotected contact with the 2 cases. Of these 49 staff, 10 had significant unprotected contact with both case 1 and case 2; 23 staff had significant unprotected contact with case 1 only; and 1 had significant unprotected contact with case 2 only. An additional 15 staff did not report significant unprotected contact, but because they shared an enclosed office space with case 1 (dotted line), they were deemed to be at higher risk of exposure and were also placed under quarantine.