More than 100,000 COVID-19 cases have been detected in the UK on a single day – a record since the pandemic began.

Although 106,122 cases were reported in the latest 24-hour period, data from the UK Health Security Agency shows 103,281 cases were identified on 15 December alone.

Cases identified have always remained a fraction of the actual infection rate in the real world. One estimate from the Scientific Advisory Group for Emergencies (SAGE), a group of scientists advising the government, suggests “hundreds of thousands of new Omicron infections per day”.

This means thousands of asymptomatic cases are likely going undetected.

One indicator of how many infections are being detected is the positivity rate, which has risen to 14.8% in England – the highest level since mid-January.

Positivity is the percentage of people who test positive for the virus of those who have been tested.

A higher positivity suggests higher transmission and that there are likely more people with coronavirus in the community who haven’t been tested yet, according to Johns Hopkins University.

Testing has been ramped up across the country to keep up with the rise in infections. More than three million people have been tested every week since early December in England – higher than at any point in the pandemic.

But the new variant’s high growth rate – doubling every two days – has meant that even the record number of tests might be stretching the limits of the government’s testing capacity.

Data shows that laboratories can test more than 250,000 additional samples every day despite processing half a million PCR tests each day over the past week.

But capacity allocated at the community level is likely to be much smaller as a large portion is reserved for testing patients and healthcare workers in hospitals.

Data also shows that the infection rate and testing capacity vary across the nation.

One in five tests in London returns positive, indicating a higher positivity rate than the England average.

Scientists suggest that due to the doubling time of Omicron, increasing the number of tests to keep up with a rise in infections will be difficult.

Kevin McConway, emeritus professor of applied statistics at the Open University, said demand for PCR tests is likely to outstrip supply within a week if cases continue to increase at the current rate.

Regardless of whether infections rise or fall in the coming weeks, scientists say that tracking COVID-19 is likely to be difficult due to the “unpredictable changes in behaviour around the festive period” during a crucial time for the pandemic.

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling we aim to better explain the world while also showing how our journalism is done.

Why data journalism matters to Sky News

Related posts:

COVID vaccines have prevented 10,400 deaths in older adults, Public Health England says PM praises Prince Philip’s ‘steadfast support’ for Queen as tributes paid to duke ‘He was our everything’: Family pays tribute to boy, 9, killed after being ‘struck by lightning’ Scotland beaten in first appearance at a major tournament in 23 years Mexico crocodile attack twin describes how she punched animal as it death rolled her sister BBC journalist abused and chased by anti-lockdown protesters in London UK daily COVID cases exceed 40,000 – highest since mid-January Children as young as 13 are being recruited by far-right extremists, says MI5 director-general Police forces to review allegations involving serving officers following Sarah Everard murder Businessman who organised fatal flight for footballer Emiliano Sala jailed for 18 months Officer investigating serial killer’s final victim was not told others had died in similar circumstances, inquest told Man charged with murdering woman in Somerset