31 January 2022
Because of the move to reporting infection episodes, today’s update will be delayed. An estimated time will be provided when available.
Cases definition to include multiple infection episodes from 31 January 2022
From 31 January 2022, UKHSA will move all COVID-19 case reporting in England to use a new episode-based definition which includes possible reinfections.
On the dashboard, this means:
cases in England by report date will change to the new definition of an episode of infection
historical numbers by report date will not be revised, so there will be a step increase in the cumulative numbers of cases on that date
specimen date metrics will be revised back to the beginning of the pandemic.
the same metric names will still be used
new metrics will show first episodes of infection (equivalent to the current case definition) and episodes of reinfection, shown by specimen date only.
UKHSA is working with the devolved administrations to align definitions across the UK.
Deaths within 28 days of positive test and deaths within 60 days of positive test will also be updated on 1 February 2022 to include deaths following the most recent episode of infection using the new episode-based case definition in England.
Additional details
As the pandemic continues and more variants emerge, it is more likely that people will be reinfected with COVID-19. Contact tracing and health protection work at UKHSA follows up people with a positive test result, whether they were a new case or a case of reinfection. However, surveillance figures only report COVID-19 cases as the date of the first infection, so individuals are only counted once.
UK public health agencies are now updating surveillance data to count infection episodes, including reinfection episodes. Infection episodes will be counted separately if there are at least 90 days between positive test results. Each episode begins with the earliest positive specimen date. If someone has another positive specimen within 90 days of the last one, this is included in the same episode. If they have another positive specimen more than 90 days after the last one, this is counted in a separate episode (a possible reinfection episode).
Cases definition to include multiple infection episodes from 31 January 2022
Sharp rise in reinfections since start of Omicron wave
Philippa Roxby
Health reporter, BBC News
Official figures on Covid were late to come out on Monday, but the dashboard has been updated now, to include reinfections – or numbers who’ve tested positive twice – going back to the start of the pandemic.
Reinfections for England and Northern Ireland have already been added in, while data for Scotland and Wales will be included in the coming days.
The updated figures show a sharp rise in people who’ve had a second positive test since the start of the Omicron wave in early December – with reinfections now making up one in 10 total infections.
These reinfections are likely to be people who were infected by Alpha or Delta and were then reinfected with the more contagious Omicron.
Reinfections have also added half a million cases to the overall total, or 4%, in England.
These reinfections are based on at least a 90-day gap between positive tests, which will rule out anyone who has been reinfected within a matter of weeks.
Deliberate Covid infections give unique insight into disease
James Gallagher
Health and science correspondent, BBC News
The world’s first Covid “challenge trial” – which deliberately infected people with the virus – has given a unique view on the early stages of the disease.
Thirty-six young and healthy volunteers all had an identical dose of Covid squirted up their nose in a hospital in London. Of those, only 18 became infected. What protected the other 16 will be the focus of future studies to understand our inherent protection against Covid.
The virus took off rapidly in those that did develop an infection, with the first symptoms and positive test results appearing within just 42 hours. The virus got a foothold first in the throat, but the levels were highest once it reached the nose. The researchers say it’s important your facemask covers both.
Symptoms were mild, but some volunteers had a prolonged loss of their sense of smell.
It is hoped challenge trials can now help develop the next generation of Covid vaccines and new anti-virals.
Google is not my friend today. I can’t find your article. Do you have a direct link to it? The link in your post goes to the front page of BBC, and I can’t find it there. I tried to Google the title. No luck. I tried to Google the title and the author. No luck.
I did find this, but I was hoping to find more information about the study, like whether the participants were vaccinated. I’m not understanding how the study could be safe if the participants weren’t vaccinated, and if they were, how that might affect the study.
Deaths definition in England updated to align with revised cases definition
From 31 January 2022, UKHSA COVID-19 case reporting has changed to an episode-based definition which includes possible reinfections.
This means that from 1 February 2022 deaths will be reported using the new episode-based case definition in England, including deaths following possible reinfections. From this point, reported deaths in people with COVID-19 (within 28 or 60 days of positive test) are considered from the first positive specimen date of the most recent episode of infection, rather than an individual’s first ever positive specimen date.
On the dashboard, this means:
reported deaths will now use the new definition in England
deaths by date of death have today been revised back to the beginning of the pandemic
historical deaths by report date have not been revised, so there is a step increase in the cumulative numbers of deaths on 1 February
the existing metric names have not changed
figures by report date for 1 February for regions and local authorities within England should not be used as they include all deaths added that day to adjust to the new definition. This file contains the correct newly reported numbers for local authorities
Caution should also be used when looking at the 7-day totals and change figures presented on the postcode search page for the next 14 days.
Additional details
UK public health agencies are now updating surveillance data to count infection episodes, including reinfection episodes. Infection episodes will be counted separately if there are at least 90 days between positive test results. Each episode begins with the earliest positive specimen date. If someone has another positive specimen within 90 days of the last one, this is included in the same episode. If they have another positive specimen more than 90 days after the last one, this is counted in a separate episode (a possible reinfection episode).
As part of the changes made, UKHSA has improved the deduplication algorithm to produce COVID-19 surveillance data in England. This has identified extra cases of infection in England that were previously removed as duplicates. These additional 173,328 cases represent around 1.5% of all infections. The additional cases reinstated by the more accurate algorithm typically had very poor identifying information, with just 25% carrying NHS numbers. This means a small number of additional deaths have been identified.
Figures for cases, deaths and tests conducted that were not reported from Scotland yesterday have been retrospectively added to the totals for 2 February 2022. The missing data have also been added to the UK figures for 2 February.
