Reducing the covid-19 isolation period in England: a policy change that needs careful evaluation
BMJ 2022; 376 doi: https://doi.org/10.1136/bmj.o184 (Published 21 January 2022) Cite this as: BMJ 2022;376:o184
- Michael Soljak, honorary clinical research fellow1,
- Azeem Majeed, professor of primary care and public health1
- 1Department of Primary Care & Public Health, Imperial College London.
- Twitter @Azeem_Majeed
How long people with covid-19 should self-isolate depends on the period for which they remain infectious. On 4 January, the US Centers for Disease Control (CDC) updated covid-19 isolation and quarantine recommendations with shorter isolation (for asymptomatic and mildly ill people) and quarantine periods of five days to focus on the period when a person is most infectious, followed by continued masking for an additional five days.1 This policy was based on a modelling study from the United Kingdom by Bays et al which showed that after the fifth day after a positive test, an estimated 31% of people remained infectious.2 All the authors of this modelling study, which was published as a pre-print on 24 December 2021, work for UK Health Security Agency (UK HSA).
On 22 December 2021, the UK HSA reduced self-isolation for covid-19 cases in England from 10 to seven days following negative lateral flow tests on days six to seven. The UK HSA stated that a seven day isolation period alongside two negative lateral flow tests had nearly the same protective effect as a 10 day …