ABSTRACT
Background: Healthcare workers (HCW) are believed to be at increased risk of SARS-CoV-2 infection. The extent of that increased risk compared to the general population and the groups most at risk have not been extensively studied. It is also not known to what extent the natural production of antibodies to SARS-CoV-2 is protective against re-infection.Methods: A prospective observational study of health and social care workers in NHS Tayside (Scotland, UK) from May to September 2020. The Siemens SARS-CoV-2 total antibody assay was used to establish seroprevalence in this cohort. Controls, matched for age and sex to the general Tayside population, were studied for comparison. New infections post antibody testing were recorded to determine if the presence of SARS-CoV-2 antibodies protect against re-infection.Results: A total of 2063 health and social care workers were recruited for this study. 300 HCW had a positive antibody test (14.5%). 11/231 control sera tested positive (4.8%). HCW therefore had an increased likelihood of a positive test (Odds ratio 3.4 95% CI 1.85-6.16, p<0.0001). Dentists, healthcare assistants and porters were the job roles most likely to test positive. Those working in front-line roles with COVID-19 patients were more likely to test positive (17.4% vs. 13.4%, p=0.02). 97.3% of patients who had previously tested positive for SARS-CoV-2 by RT-PCR had positive antibodies. 18.7% of HCW had an asymptomatic infection. There were 38 new infections with SARS-CoV-2 in HCW who were previously antibody negative and 1 symptomatic RT-PCR positive re-infection in a HCW who had detectable antibodies 76 days prior to re-infection. The presence of antibodies was therefore associated with an 85% reduced risk of re-infection with SARS-CoV-2 (HR 0.15, 95% CI 0.06 to 0.35, p=0.026).Conclusion: In this study, HCW were three times more likely to test positive for SARS-CoV-2 than the general population. Almost all of the infected individuals developed an antibody response and this was 85% effective in protecting against re-infection with SARS-CoV-2.Funding Statement: NHS Tayside COVID-19 Research Fund, JDC is supported by the British Lung Foundation Chair of Respiratory Research.Declaration of Interests: JDC reports grants and personal fees from GlaxoSmithKline, Boehringer-Ingelheim, Astrazeneca, Pfizer, Bayer Healthcare, Grifols, Napp, Insmed and Zambon outside the submitted work; All other authors report no conflicts of interest.Ethics Approval Statement: West of Scotland Research Ethics committee, approval number 20/WS/0078.
Subject(s)
COVID-19 , Williams SyndromeABSTRACT
Introduction: Healthcare workers are believed to be at increased risk of SARS-CoV-2 infection. The extent of that increased risk compared to the general population and the groups most at risk have not been extensively studied. Methods: A prospective observational study of health and social care workers in NHS Tayside (Scotland, UK) from May to September 2020. The Siemens SARS-CoV-2 total antibody assay was used to establish seroprevalence in this cohort. Patients provided clinical information including demographics and workplace information. Controls, matched for age and sex to the general Tayside population, were studied for comparison. Results: A total of 2062 health and social care workers were recruited for this study. The participants were predominantly female (81.7%) and 95.2% were white. 299 healthcare workers had a positive antibody test (14.5%). 11 out of 231 control sera tested positive (4.8%). Healthcare workers therefore had an increased likelihood of a positive test (odds ratio 3.4 95% CI 1.85-6.16, p<0.0001). Dentists, healthcare assistants and porters were the job roles most likely to test positive. Those working in front-line roles with COVID-19 patients were more likely to test positive (17.4% vs. 13.4%, p=0.02). 97.1% of patients who had previously tested positive for SARS-CoV-2 by RT-PCR had positive antibodies, compared to 11.8% of individuals with a symptomatic illness who had tested negative. Anosmia was the symptom most associated with the presence of detectable antibodies. Conclusion: In this study, healthcare workers were three times more likely to test positive for SARS-CoV-2 than the general population. The seroprevalence data in different populations identified in this study will be useful to protect healthcare staff during future waves of the pandemic.
Subject(s)
COVID-19ABSTRACT
Healthcare associated transmission of viral infections is a major problem that has significant economic costs and can lead to loss of life. Infections with the highly contagious SARS-CoV-2 virus have been shown to have a high prevalence in hospitals around the world. The spread of this virus might be impacted by the density of patients inside hospital bays. To investigate this aspect, in this study we consider a mathematical modelling and computational approach to describe the spread of SARS-CoV-2 among hospitalised patients. We focus on 4-bed bays and 6-bed bays, which are commonly used to accommodate various non-Covid-19 patients in many hospitals across UK. We use this mathematical model to investigate the spread of SARS-CoV-2 infections among patients in non-Covid bays, in the context of various scenarios: changes in the number of contacts with infected patients and staff, having symptomatic vs. asymptomatic patients, removing infected individuals from these hospital bays once they are known to be infected, and the role of periodic testing of hospitalised patients. Our results show that 4-bed bays reduce the spread of SARS-CoV-2 compared to 6-bed bays. Moreover, we show that the position of a new (not infected) patient in specific beds in a 6-bed bay might also slow the spread of the disease. Finally, we propose that regular SARS-CoV-2 testing of hospitalised patients would allow appropriate placement of infected patients in specific (Covid-only) hospital bays.
Subject(s)
COVID-19ABSTRACT
It has been recognised that health and social care workers (HSCW) experience higher rates of infection with SARS-CoV-2. Widespread testing of HSCWs and their symptomatic household contacts (SHCs) has not been fully implemented in the United Kingdom. We describe the results of a testing programme for HSCWs and SHCs in a single UK region (Tayside, Scotland). The testing service was established 17 th March 2020 as the first in the country, and samples were collected at a drive-through testing hub based at a local community hospital. HSCWs with mild symptoms who were self-isolating and the SHCs of HSCWs who would therefore be absent from work attended for testing. From 17 th March 2020 to 11 th April, 1887 HSCWs and SHCs underwent testing. Clinical information was available for 1727 HSCWs and SHCs. 4/155 (2.6%) child contacts, 73/374 (19.5%) adult contacts and 325/1173 (27.7%) HSCWs tested positive for SARS-CoV-2. 15 of 188 undetermined cases were positive (8.0%). We estimate that testing prevented up to 3634 lost work days from HSCW testing, 2795 from adult SHC testing and 1402 lost work days from child SHC testing. The establishment of this testing programme has assisted the infection prevention and control team in their investigation of transmission and supported adequate staffing in health and social care sectors.