Imperial College London
Alternate

Professor Neil Ferguson

Faculty of Medicine, School of Public Health

Director of the School of Public Health
 
 
 
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Contact

 

+44 (0)20 7594 3296neil.ferguson Website

 
 
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Location

 

508School of Public HealthWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@techreport{Ferguson:2021:10.25561/93035,
author = {Ferguson, N and Ghani, A and Hinsley, W and Volz, E and on, behalf of the Imperial College COVID-19 Response Team},
doi = {10.25561/93035},
title = {Report 50: Hospitalisation risk for Omicron cases in England},
url = {http://dx.doi.org/10.25561/93035},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - RPRT
AB  - To assess differences in the risk of hospitalisation between the Omicron variant of concern  (1) and the Delta  variant,  we  analysed  data  from  all  PCR-confirmed  SARS-CoV-2  cases  in  England  with  last  test specimen dates between 1st and 14th December inclusive. Variant was defined using a combination of S-gene  Target  Failure  (SGTF)  and  genetic  data.    Case  data  were  linked  by  National  Health  service  (NHS) number to the National Immunisation Management System (NIMS) database, the NHS Emergency Care (ECDS) and Secondary Use Services (SUS) hospital episode datasets. Hospital attendance was defined as any record of attendance at a hospital by a case in the 14 days following their last positive PCR test, up to and  including  the  day  of  attendance.  A  secondary  analysis  examined  the  subset  of  attendances  with  a length  of  stay  of  one  or  more  days.  We  used  stratified  conditional  Poisson  regression  to  predict hospitalisation  status,  with demographic  strata  defined  by  age,  sex,  ethnicity,  region,  specimen  date, index of multiple deprivation and in some analyses, vaccination status. Predictor variables were variant (Omicron or Delta), reinfection status and vaccination status.  Overall,  we  find  evidence  of  a  reduction  in  the  risk  of  hospitalisation  for  Omicron  relative  to  Delta infections, averaging over all cases in the study period. The extent of reduction is sensitive to the inclusion criteria  used  for  cases  and  hospitalisation,  being  in  the  range  20-25%  when  using  any  attendance  at hospital as the endpoint, and 40-45% when using hospitalisation lasting 1 day or longer or hospitalisations with the ECDS discharge field recorded as “admitted” as the endpoint (Table 1). These reductions must be balanced against the larger risk of infection with Omicron, due to the reduction in protection provided by both vaccination and natural infection. A previous infection reduces the
AU  - Ferguson,N
AU  - Ghani,A
AU  - Hinsley,W
AU  - Volz,E
AU  - on,behalf of the Imperial College COVID-19 Response Team
DO  - 10.25561/93035
PY  - 2021///
TI  - Report 50: Hospitalisation risk for Omicron cases in England
UR  - http://dx.doi.org/10.25561/93035
UR  - https://www.imperial.ac.uk/media/imperial-college/medicine/mrc-gida/2021-12-22-COVID19-Report-50.pdf
UR  - http://hdl.handle.net/10044/1/93035
ER  -
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