Hospital outbreaks of COVID19 result in considerable mortality and disruption to healthcare services and yet little is known about transmission within this setting. We characterise within hospital transmission by combining viral genomic and epidemiological data using Bayesian modelling amongst 2181 patients and healthcare workers from a large UK NHS Trust. Transmission events were compared between Wave 1 (1st March to 25th July 2020) and Wave 2 (30th November 2020 to 24th January 2021). We show that staff-to-staff transmissions reduced from 31.6% to 12.9% of all infections. Patient-to-patient transmissions increased from 27.1% to 52.1%. 40%-50% of hospital-onset patient cases resulted in onward transmission compared to 4% of community-acquired cases. Control measures introduced during the pandemic likely reduced transmissions between healthcare workers but were insufficient to prevent increasing numbers of patient-to-patient transmissions. As hospital-acquired cases drive most onward transmission, earlier identification of nosocomial cases will be required to break hospital transmission chains.
Tang and his colleagues compared hospitalised, community and staff Coronavirus disease 2019 (COVID-19) infection rates during the early phase of the evolving COVID-19 epidemic [1] , but an emerging factor is the ethnicity of individuals. In this letter, we report our investigation into the potential associations between ethnicity and COVID-19. Despite only 15% of the UK population being from black and ethnic minority (BAME) backgrounds [2] , recent data has identified that 34% of patients admitted to intensive care (ITU) with COVID-19 belong to BAME groups [3] . The potential difference in outcomes associated with ethnicity for patients with COVID-19 has caused concern within the scientific community, with many calling for further research [ 4 , 5 ].Consequently, we analysed routinely collected data from adult patients at Sheffield Teaching Hospitals (STH) between 01/03/20 and 25/04/20. Ethnicities were categorised into BAME (including Black, Asian-subcontinent, mixed and any other non-White background), White and Not Known. A total of 3018 patients were tested for COVID-19, of whom 1493 were female and 1499 male (26 gender-unknown). Median age for BAME patients was 54 years and for White patients was 71 years.Overall data showed that of the 3018 patients tested, 806(26 • 7%) were positive for COVID-19, including 95 from a BAME and 631 from a White background ( Table 1 ). BAME patients were significantly more likely to test positive than the White cohort (X 2 (1, n = 726) = 4 • 9561, p = • 026). Whilst there was an almost equal gender split in terms of population tested, men were significantly more likely to test positive than women ((X 2 (1, n = 2922) = 16 • 90,189, p < • 0 0,0 01). BAME men were significantly more likely to test positive compared to both BAME women (X 2 (1, n = 296) = 7 • 2608, p = • 007) and White men (X 2 (1, n = 1349) = 6 • 7514, p = • 009). Furthermore, positive BAME patients were significantly younger than White patients, with a median age of 55 years compared to 77 years (Mann-Whitney U = 15,155, p < • 001 two-tailed).Of positive patients, 755 were admitted to hospital for further treatment or were tested whilst inpatient. There was no significant difference between BAME and White groups in terms of overall admissions (X2(1, n = 726) = 3 • 0032, p = • 083). BAME inpatients were, however, significantly more likely to be admitted to ITU compared to White inpatients (X2(1, n = 695) = 23 • 977, p < • 0 0,0 01). After age adjustment, black (2 • 97, p = • 010) and sub-continental groups (2 • 43, p = • 087) had much higher odds than the white cohort (1) for ITU admission. Whilst men accounted for just over half (450/806
Objectives - To characterise within-hospital SARS-CoV-2 transmission across two waves of the COVID-19 pandemic. Design - A retrospective Bayesian modelling study to reconstruct transmission chains amongst 2181 patients and healthcare workers using combined viral genomic and epidemiological data. Setting - A large UK NHS Trust with over 1400 beds and employing approximately 17,000 staff. Participants - 780 patients and 522 staff testing SARS-CoV-2 positive between 1st March 2020 and 25th July 2020 (Wave 1); and 580 patients and 299 staff testing SARS-CoV-2 positive between 30th November 2020 and 24th January 2021 (Wave 2). Main outcome measures - Transmission pairs including who-infected-whom; location of transmission events in hospital; number of secondary cases from each individual, including differences in onward transmission from community and hospital onset patient cases. Results - Staff-to-staff transmission was estimated to be the most frequent transmission type during Wave 1 (31.6% of observed hospital-acquired infections; 95% CI 26.9 to 35.8%), decreasing to 12.9% (95% CI 9.5 to 15.9%) in Wave 2. Patient-to-patient transmissions increased from 27.1% in Wave 1 (95% CI 23.3 to 31.4%) to 52.1% (95% CI 48.0 to 57.1%) in Wave 2, to become the predominant transmission type. Over 50% of hospital-acquired infections were concentrated in 8/120 locations in Wave 1 and 10/93 locations in Wave 2. Approximately 40% to 50% of hospital-onset patient cases resulted in onward transmission compared to less than 4% of definite community-acquired cases. Conclusions - Prevention and control measures that evolved during the COVID-19 pandemic may have had a significant impact on reducing infections between healthcare workers, but were insufficient during the second wave to prevent a high number of patient-to-patient transmissions. As hospital-acquired cases appeared to drive most onward transmissions, more frequent and rapid identification and isolation of these cases will be required to break hospital transmission chains in subsequent pandemic waves
25th J'uly 2020", which has been corrected to "25th July 2020".In the main text and References, the phrase "Identifying within-hospitalSARS-CoV-2 transmission" was missing a space between "hospital" and "SARS-CoV-2", which has been corrected to "Identifying within-hospital SARS-CoV-2 transmission".In the main text, there were two uses of the phrase "hospital-acquiredSARS-CoV-2 infections" which were also missing a space between "acquired" and "SARS-CoV-2", which have been corrected to "hospital-acquired SARS-CoV-2 infections".In Table 1, there was an additional space in "Community onset-community associated", which has been corrected to "Community onset-community associated". These corrections have been made in both the PDF and HTML versions of the Article.
LINKED CONTENTThis article is linked to Chaudhary et al and Chaudhary & Stanley papers. To view these articles, visit https://doi.org/10.1111/apt.16170 and https://doi.org/10.1111/apt.16368
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.