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expert reaction to news that data collection for the ONS COVID-19 Infection Survey is to be paused from 31 March 2023

A press release from the UK Health Security Agency (UKHSA) has announced that data collection for the COVID-19 Infection Survey will be paused.


Prof Sheila Bird, formerly Programme Leader, MRC Biostatistics Unit and Honorary Professor, Edinburgh University’s College of Medicine and Veterinary Medicine, said:

“Today’s announcement on the “pausing” of ONS Community Infection Survey is right to start by thanking the survey’s 500,000 participants but fails to mention that they were a minority of those invited to take part.

“The participation-rate in important public health surveillance studies needs to be much higher, ideally over 60%, and to achieve that survey-design has to be manageable by and acceptable to the majority of those invited to take part.

“We are told that:  “The data collected will continue to be valuable for many years to learn more about how COVID-19 infection and vaccination affect future health outcomes.

“At some stage ONS-CIS will have asked its participants for their permission for ongoing linkage to participants’ GP-records, vaccination-records and hospitalization-records. The consent-rate for record-linkage is additional to participants’ consent for SARS-CoV-2 surveillance and so the follow-up cohort may be 400,000 or fewer (if the consent-rate for linkage was 80% or less).

“The pause is signalled on grounds of cost-efficiency rather than pandemic-preparedness as that latter requires a maintained, funded, well-functioning, high response-rate, adaptable background surveillance set-up which almost always will involve a laboratory-network and a personal identifier.

“The focus on cost-efficiency in today’s announcement makes all the more surprising the earlier policy decision to cease funding for England’s highly cost-efficient REACT surveillance: perchance because REACT was not UK-wide. Neither ONS-CIS nor REACT achieved over 40% participation-rates, let alone 60%: but the cost-per participant was an order of magnitude lower for REACT.

“Public, press and parliament, let alone scientists, should ensure that the forthcoming review offers a defendable scientific rationale for any policy recommendations it comes up with.

“The statisticians, epidemiologists, laboratory-teams and survey-teams who delivered ONS-CIS and REACT have a wealth of experience and expertise and deserve nothing less – as do potential participants in key national surveillance studies.”


Prof Kevin McConway, Emeritus Professor of Applied Statistics, The Open University, said:

“Covid certainly hasn’t disappeared.  Last week’s release from the ONS Covid-19 Infection Survey (CIS) estimated that about one and a half million people would have tested positive in the UK in the week ending 21 February, 280 deaths coded as being due to Covid were registered in England and Wales in the most recent week available (ending 24 February), and there are around 7,500 patients in hospital in England with Covid, with around 900 being admitted daily.  So does it make sense to ‘pause’ data collection for the admirable ONS CIS after the end of this month?

“There is no doubt that the ONS survey has done a magnificent job over the last three years in organising and collecting swab test results from the UK household population, and (with academic partners) analysing the resulting data and publishing the results in many informative ways.  There hasn’t been an equivalent anywhere else.

“But other countries have managed without a survey like that, and in the UK we don’t have surveillance systems that work in a similar way for other important infectious diseases such as influenza.  Surveillance of a very wide range of infectious diseases does, of course, go on, through the UK Health Security Agency and other bodies in the devolved administrations.  For instance, there has been a long-running series of weekly reports (at least during the winter flu seasons) on influenza and other respiratory infectious diseases, and this was expanded early in the pandemic to be published throughout the year and to cover Covid explicitly, as well as the other diseases that it always covered1.  These reports put together data from a variety of smaller surveys and other data sources, and they have generally been effective over the years in monitoring flu, for example.

“However, the announcement about pausing the CIS doesn’t make it clear what is actually going to happen about Covid surveillance after data collection from the ONS CIS is paused.  We’re told that Covid surveillance is being ‘actively reviewed’ and details of any new surveillance surveys will be confirmed ‘in due course’.  While it’s important to balance out the available resource across many potential infectious disease threats, I’d be happier with the decision to pause the CIS if I knew more about what might replace it in three weeks.”




All our previous output on this subject can be seen at this weblink:



Declared interests

Prof Sheila Bird chairs the Royal Statistical Society’s Working Party on Performance Monitoring in the Public Services.

Prof Kevin McConway: “I am a Trustee of the SMC and a member of its Advisory Committee.  My quote above is in my capacity as an independent professional statistician.”



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