This site is intended for health professionals only

Winter Covid-19 Infection Study to track infection rates in the community

Winter Covid-19 Infection Study to track infection rates in the community

A new study has been launched to gather vital information over the winter on the Covid-19 virus, the UK Health Security Agency (UKHSA) has announced.

The Winter Covid-19 Infection Study (WCIS), involving up to 200,000 people, will run from November 2023 until March 2024 and will be jointly run by UKHSA and the Office for National Statistics (ONS).

During the pandemic, the ONS and scientific experts at Oxford University ran the Covid-19 Infection Study (CIS). This became a gold standard of Covid-19 surveillance studies and allowed accurate monitoring of the virus. Through the analysis of over 11.5 million swab tests and 3 million blood tests between April 2020 and March 2023, transmission patterns and infection rates were monitored.

The new winter study will analyse 32,000 lateral flow tests, which will be undertaken weekly to monitor Covid-19 infections circulating in the community. The tests will be sent to a representative selection of the population. Initial testing has taken place at the Porton Down laboratory and show that the lateral flow tests are effective at detecting the newest variant of Covid-19, BA 2.86.

As a result of the vaccine programmes, Covid-19 has become a virus that we are able to live with. There are, however, vulnerable people in the community for whom the virus remains a serious and dangerous threat, causing severe illness and hospitalisation, leading to increased pressure on the NHS services throughout the winter.

The existing system of Covid-19 surveillance, which is run by the UKHSA, gives up-to-date information on hospital and intensive care unit (ICU) admission rates due to Covid-19 infections. The latest results, published for the seven days before and including 28 September 2023, show that 12,187 people in England tested positive for Covid-19. This is an increase of 13.7 per cent compared to the previous week.

The Government’s weekly Flu and Covid-19 report states that ‘In week 38 [18-24 September 2023], from most indicators, influenza activity remained low and stable. Covid-19 activity remained stable across most indicators, although an increase was observed in emergency department (ED) attendances.’

The new WCIS will add to this data and detect changes in the infection hospitalisation rate (IHR). The IHR is the proportion of hospitalisations from the total of infected individuals and can provide a good estimate of the impact of the virus on the community. The data will highlight any changes in the way the virus is spreading, which could be driven by the emergence of new variants and will help to predict the potential winter demand on the NHS.

Professor Steven Riley, director general of data, analytics and surveillance at UKHSA, said: ‘The data we collected alongside the ONS during the pandemic provided us with a huge amount of valuable insight, so I am delighted that we are able to work together again to keep policymakers and the wider public informed in the coming months. UKHSA continues to lead the way internationally on Covid-19 surveillance and by re-introducing a study of positivity in the community, ‘we can better detect changes in the behaviour of the virus’.

Deputy national statistician Emma Rourke at the ONS added: ‘There remains a need for robust data to help us continue to understand the virus and its effects during the winter months. As well as working to provide UKHSA with regular rates of positivity, we will also be looking at analysis of symptoms, risk factors and the impact of respiratory infections, including long Covid, as part of this important surveillance.’


See how our symptom tool can help you make better sense of patient presentations
Click here to search a symptom