key: cord-0751545-y72r3cgw
authors: Wee, Liang En; Conceicao, Edwin Philip; Sim, Xiang Ying Jean; Aung, May Kyawt; Tan, Kwee Yuen; Wong, Hei Man; Wijaya, Limin; Tan, Ban Hock; Ling, Moi Lin; Venkatachalam, Indumathi
title: Minimising intra-hospital transmission of COVID-19: the role of social distancing
date: 2020-04-12
journal: J Hosp Infect
DOI: 10.1016/j.jhin.2020.04.016
sha: f247a21e5d372dffb645d607776fa2e2ad1ab174
doc_id: 751545
cord_uid: y72r3cgw

nan

Singhealth Infectious Diseases Residency, Singapore 10 2. Department of Infectious Diseases, Singapore General Hospital, Singapore 11

3. Department of Infection Prevention and Epidemiology, Singapore General Hospital, Singapore 12 13 This work was not grant-funded. 23

The authors report no conflicts of interest. hospitalised inpatients with suspected COVID-19 is important to reduce the likelihood of nosocomial spread. 35

However, patients with COVID-19 may present with respiratory syndromes indistinguishable from those 36 caused by common respiratory viruses. [1] This poses a challenge for early isolation and containment, 37 especially during significant ongoing community transmission. While isolation ward beds are prioritized for 38 suspected COVID-19 cases, unsuspected cases of COVID-19 without suspicious contact or travel history 39 may initially be nursed outside of dedicated isolation wards prior to detection. Given that patients outside the 40 isolation ward may not be subject to movement restrictions and share common facilities, social mingling 41 represents a potential route for nosocomial spread, especially as COVID-19 cases may present with mild 42 symptoms and remain relatively well. [1] While social distancing has been identified as crucial for containment 43 in the community, [2] social distancing within hospitals is equally vital in reducing nosocomial spread, 44 especially in hospitals where the majority of patients are nursed in multi-bedded cohort rooms, rather than in 45 single-occupancy rooms. 46

In Singapore, a globalised Asian city-state, the first imported case of COVID-19 was reported in end-January 48 2020; followed by the first case of local transmission in early February 2020.

[3] At our institution, the 49 Singapore General Hospital (SGH), the isolation ward was reserved for confirmed/suspected cases of 50 COVID-19. However, given rising numbers of locally-transmitted cases, from 4 February, our institution 51 placed individuals admitting with respiratory symptoms but without suspicious contact or travel history in 52 respiratory surveillance wards (RSWs) where COVID-19 was first excluded and healthcare workers (HCWs) 53 used full personal protective equipment (PPE) including N95 masks, disposable gowns, gloves and 54 faceshields. Despite this resource-intensive containment effort, it was recognised that some cases of COVID-55 19 with mild symptoms might be initially admitted to the general ward. Our institution therefore emphasised 56 hospital-wide social distancing measures. For patients admitting to the RSW, as the risk of a potentially 57 unsuspected case of COVID-19 was higher, patients were advised to avoid mingling and to wear surgical 58 spaced at least ~2 metres apart, and partitions were placed between patient beds (Figure 1 ). In the general 61 ward, shared communal facilities (eg. day rooms) were closed during the duration of the ongoing COVID-19 62 outbreak, and patients were limited to one visitor at any time. HCWs in the general ward wore surgical masks. 63

Hospital-wide, in common areas such as waiting areas, pharmacies, food and retail outlets, patients were 64 directed to keep one metre apart from one another, using visual cues (eg. floor markings and markings on 65 seats) to guide waiting and queuing in both seated and standing areas. 66 67 Over a 3-month period from 4 January to 4 April 2020, a total of 75 confirmed cases of COVID-19 were 68 diagnosed in our institution. While the majority of cases (84.0%, 63/75) were admitted to isolation wards, 12 69 cases of COVID-19 were initially admitted outside of the isolation ward. Of these, the majority (91.6%, 70 11/12) were admitted to the RSW. One patient was initially admitted to the general ward and nursed in a 71 cohorted cubicle with 5 other patients, as respiratory symptoms were initially mild. The patient was 72 transferred to an RSW 19 hours after admission, where the diagnosis of COVID-19 was made. At diagnosis, 73 the cycle threshold (Ct) value for SARS-CoV-2 on rt-PCR (polymerase chain reaction) testing of 74 oropharyngeal swab samples was 18, an inverse surrogate for high viral load and potential infectivity; this was 75 in keeping with data suggesting peak viral shedding in the first week of symptoms. [4] A total of 18 patients in 76 the general ward and 2 patients in the RSW had shared a room or common toilet with the index case; all were 77 deemed to be exposed, (Figure 1 ) given potential contamination of the shared air and surface environment 78 from droplet and fomite spread.

[5] A total of 8 HCWs in the general ward had cared for the patient while 79 wearing surgical masks. However, none of the exposed patients or HCWs developed COVID-19 within the 80 estimated incubation period, [6] despite being closely followed up for 14 days. Of note, the patient had 81 complied with social distancing measures and had not interacted with any of the other exposed patients. At 82 the patient's initiative, he had worn a mask throughout the admission as an added precaution to minimise 83 infection. 84 

Social distancing outside general ward: increased distance in indoor and outdoor seating areas

Clinical Characteristics of Coronavirus Disease 2019 in China

Isolation, quarantine, social distancing and community 104 containment: pivotal role for old-style public health measures in the novel coronavirus (2019-105 nCoV) outbreak

COVID-19 in Singapore-Current Experience: Critical Global Issues That 107

Require Attention and Action

Virological 109 assessment of hospitalized patients with COVID-2019

Surface Environmental, 112 and Personal Protective Equipment Contamination by Severe Acute Respiratory Syndrome 113 Coronavirus 2 (SARS-CoV-2) From a Symptomatic Patient

The Incubation Period of Coronavirus Disease

From Publicly Reported Confirmed Cases: Estimation and Application

The authors thank our colleagues for the unstinting efforts against COVID-19. 98 99 100