Transmission of community- and hospital-acquired SARS-CoV-2 in hospital settings in the UK: A cohort study.

BACKGROUND: Nosocomial spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been widely reported, but the transmission pathways among patients and healthcare workers (HCWs) are unclear. Identifying the risk factors and drivers for these nosocomial transmissions is critical for infection prevention and control interventions. The main aim of our study was to quantify the relative importance of different transmission pathways of SARS-CoV-2 in the hospital setting. METHODS AND FINDINGS: This is an observational cohort study using data from 4 teaching hospitals in Oxfordshire, United Kingdom, from January to October 2020. Associations between infectious SARS-CoV-2 individuals and infection risk were quantified using logistic, generalised additive and linear mixed models. Cases were classified as community- or hospital-acquired using likely incubation periods of 3 to 7 days. Of 66,184 patients who were hospitalised during the study period, 920 had a positive SARS-CoV-2 PCR test within the same period (1.4%). The mean age was 67.9 (±20.7) years, 49.2% were females, and 68.5% were from the white ethnic group. Out of these, 571 patients had their first positive PCR tests while hospitalised (62.1%), and 97 of these occurred at least 7 days after admission (10.5%). Among the 5,596 HCWs, 615 (11.0%) tested positive during the study period using PCR or serological tests. The mean age was 39.5 (±11.1) years, 78.9% were females, and 49.8% were nurses. For susceptible patients, 1 day in the same ward with another patient with hospital-acquired SARS-CoV-2 was associated with an additional 7.5 infections per 1,000 susceptible patients (95% credible interval (CrI) 5.5 to 9.5/1,000 susceptible patients/day) per day. Exposure to an infectious patient with community-acquired Coronavirus Disease 2019 (COVID-19) or to an infectious HCW was associated with substantially lower infection risks (2.0/1,000 susceptible patients/day, 95% CrI 1.6 to 2.2). As for HCW infections, exposure to an infectious patient with hospital-acquired SARS-CoV-2 or to an infectious HCW were both associated with an additional 0.8 infection per 1,000 susceptible HCWs per day (95% CrI 0.3 to 1.6 and 0.6 to 1.0, respectively). Exposure to an infectious patient with community-acquired SARS-CoV-2 was associated with less than half this risk (0.2/1,000 susceptible HCWs/day, 95% CrI 0.2 to 0.2). These assumptions were tested in sensitivity analysis, which showed broadly similar results. The main limitations were that the symptom onset dates and HCW absence days were not available. CONCLUSIONS: In this study, we observed that exposure to patients with hospital-acquired SARS-CoV-2 is associated with a substantial infection risk to both HCWs and other hospitalised patients. Infection control measures to limit nosocomial transmission must be optimised to protect both staff and patients from SARS-CoV-2 infection.

Absence of COVID-19 Infection in Patients Accessing IBD Unit at Humanitas, Milan: Implications for Postlockdown Measures.

INTRODUCTION: The risk of coronavirus disease-19 infection for healthcare professionals and patients in hospitals remains unclear. METHODS: We investigated whether precautions adopted in our inflammatory bowel disease (IBD) unit have minimized the risks of infection for all patients accessing our facilities in a 1-month period by assessing the rate of coronavirus disease-19 infection in the follow-up period. RESULTS: Three hundred-twenty patients with IBD were included. None were infected from severe acute respiratory syndrome-coronavirus 2 in the follow-up period. None of the IBD team members were infected. DISCUSSION: Neither pharmacological immunosuppression nor access to the hospital seem to be risk factors for infection in patients with IBD.

COVID-19 emergency response assessment study: a prospective longitudinal survey of frontline doctors in the UK and Ireland: study protocol.

INTRODUCTION: The COVID-19 pandemic is putting an unprecedented strain on healthcare systems globally. The psychological impact on frontline doctors of dealing with the COVID-19 pandemic is currently unknown. This longitudinal professional survey aims to understand the evolving and cumulative effects of working during the COVID-19 outbreak on the psychological well-being of doctors working in emergency departments (ED), intensive care units (ICU) and anaesthetics during the pandemic. METHODS AND ANALYSIS: This study is a longitudinal questionnaire-based study with three predefined time points spanning the acceleration, peak and deceleration phases of the COVID-19 pandemic.The primary outcomes are psychological distress and post-trauma stress as measured by the General Health Questionnaire-12 (GHQ-12) and Impact of Events Scale-Revised (IES-R). Data related to personal and professional characteristics will also be collected. Questionnaires will be administered prospectively to all doctors working in ED, ICU and anaesthetics in the UK and Ireland via existing research networks during the sampling period. Data from the questionnaires will be analysed to assess the prevalence and degree of psychological distress and trauma, and the nature of the relationship between personal and professional characteristics and the primary outcomes. Data will be described, analysed and disseminated at each time point; however, the primary endpoint will be psychological distress and trauma at the final time point. ETHICS AND DISSEMINATION: Ethical approval was obtained from the University of Bath, UK (ref: 4421), and Children's Health Ireland at Crumlin, Ethics Committee. Regulatory approval from the Health Regulation Authority (UK), Health and Care Research Wales (IRAS: 281944).This study is limited by the fact that it focuses on doctors only and is survey based without further qualitative interviews of participants. It is expected this study will provide clear evidence of the psychological impact of COVID-19 on doctors and will allow present and future planning to mitigate against any psychological impact. TRIAL REGISTRATION NUMBER: ISRCTN10666798.

A cross-sectional study of immune seroconversion to SARS-CoV-2 in frontline maternity health professionals.

COVID-19, the respiratory disease caused by SARS-CoV-2, is thought to cause a milder illness in pregnancy with a greater proportion of asymptomatic carriers. This has important implications for the risk of patient-to-staff, staff-to-staff and staff-to-patient transmission among health professionals in maternity units. The aim of this study was to investigate the prevalence of previously undiagnosed SARS-CoV-2 infection in health professionals from two tertiary-level maternity units in London, UK, and to determine associations between healthcare workers' characteristics, reported symptoms and serological evidence of prior SARS-CoV-2 infection. In total, 200 anaesthetists, midwives and obstetricians, with no previously confirmed diagnosis of COVID-19, were tested for immune seroconversion using laboratory IgG assays. Comprehensive symptom and medical histories were also collected. Five out of 40 (12.5%; 95%CI 4.2-26.8%) anaesthetists, 7/52 (13.5%; 95%CI 5.6-25.8%) obstetricians and 17/108 (15.7%; 95%CI 9.5-24.0%) midwives were seropositive, with an overall total of 29/200 (14.5%; 95%CI 9.9-20.1%) of maternity healthcare workers testing positive for IgG antibodies against SARS-CoV-2. Of those who had seroconverted, 10/29 (35.5%) were completely asymptomatic. Fever or cough were only present in 6/29 (21%) and 10/29 (35%) respectively. Anosmia was the most common symptom occurring in 15/29 (52%) seropositive participants and was the only symptom that was predictive of positive seroconversion (OR 18; 95%CI 6-55). Of those who were seropositive, 59% had not self-isolated at any point and continued to provide patient care in the hospital setting. This is the largest study of baseline immune seroconversion in maternity healthcare workers conducted to date and reveals that one out of six were seropositive, of whom one out of three were asymptomatic. This has significant implications for the risk of occupational transmission of SARS-CoV-2 for both staff and patients in maternity units. Regular testing of staff, including asymptomatic staff should be considered to reduce transmission risk.

What proportion of healthcare worker masks carry virus? A systematic review.

OBJECTIVE: Concerns have been raised by healthcare organisations in New Zealand that routine mask use by healthcare workers (HCW) may increase the risk of transmission of SARS-CoV-2 through increased face touching. Routine mask use by frontline HCW was not recommended when seeing 'low risk' patients. The aim of this review was to determine the carriage of respiratory viruses on facemasks used by HCW. METHODS: A systematic review was conducted with structured searches of medical and allied health databases. Two authors independently screened articles for inclusion, with substantial agreement (k = 0.66, 95% CI 0.54-0.79). Studies that at least one author recommended for full text review were reviewed in full for inclusion. Two authors independently extracted data from included studies including the setting, method of analysis and results. There was exact agreement on the proportion of virus detected on masks. RESULTS: We retrieved 1233 titles, 47 underwent full text review and five studies reported in four articles were included. The studies were limited by small numbers and failure to test all eligible masks in some studies. The proportion in each study ranged from 0 (95% CI 0-10) to 25% (95% CI 8-54). No study reported clinical respiratory illness as a result of virus on the masks. CONCLUSIONS: Although limited, current evidence suggests that viral carriage on the outer surface of surgical masks worn by HCW treating patients with clinical respiratory illness is low and there was not strong evidence to support the assumption that mask use may increase the risk of viral transmission.

Risk of SARS-CoV-2 transmission to medical staff and patients from an exposure to a COVID-19-positive ophthalmologist.

PURPOSE: To evaluate the risk of transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after exposure to a COVID-19+ physician in a retina clinic. METHODS: A retrospective observational study. Records of 142 patients and 11 staff members from a single retina clinic that were exposed to a COVID-19+ ophthalmologist were reviewed. All 153 individuals were placed in quarantine for 14 days. They were contacted after the quarantine period to inquire about symptoms consistent with COVID-19, and the results of diagnostic test for SARS-CoV-2 when performed. RESULTS: All patients (n = 142) were contacted successfully. The mean age was 72.8 ± 13.6 years; 54.2% (n = 77) were females. Twenty-three patients (16.2%) were exposed during an ophthalmic exam, 111 (78.2%) during intraocular injection, 4 (2.8%) underwent exam and injection, 3 (2.1%) underwent surgery, and one patient (0.7%) had laser photocoagulation. Half of the patients (50%; n = 71) were in contact with the COVID-19+ physician while he was symptomatic. Forty-four patients (31%) wore a mask on the day of their visit. 11.3% (n = 16) of the patients, and all involved staff had been tested for the virus and all were negative. One patient (0.7%) reported transient cough and sore throat, and the remaining 141 (99.3%) patients and 11 (100%) staff did not develop symptoms. CONCLUSIONS: Low risk for SARS-CoV-2 transmission in the ophthalmic setting was observed when universal safety measures such as social distancing, meticulous hand hygiene, enlarged breath shields, and mask wear during procedures were taken.