Updated 9th April 2022

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Is this the start of the third wave?

Written byZOE Editorial Staff

    According to the ZOE COVID Symptom Study UK Infection Survey figures based on swab tests data from up to five days ago, daily new cases of COVID-19 in the UK are rising again but there are big differences between regions. Regions like Wales and London are seeing sharp rises, whereas in  the North East and Yorkshire cases are still falling, and others are rising slowly. 

    Key findings from ZOE COVID Symptom Study UK Infection Survey this week: 

    • There are currently 26,897 daily new symptomatic cases of COVID in the UK on average over the two weeks up to 13 December (excluding care homes) 

    • This compares to 19,190 daily new symptomatic cases a week ago

    • The UK R value is 1.1.

    • Regional R values are: England, 1.1. Wales, 1.2. Scotland, 0.9. (full table below) 

    • Wales with an R value of 1.2 now has more cases than at the peak of its second wave before the firebreaker and is still rising rapidly with more cases than anywhere else in the UK

    • In London, where cases never truly peaked since April, the number of daily new cases is climbing again and nearly 10 percent of tests are positive. There are wide six fold differences across the boroughs. Enfield, Havering and Merton are the worst affected areas. Westminster, Kingston upon Thames and Hounslow are the least affected areas (see a map and a graph of for London below)

    • In most other UK regions, cases are either steady or rising, the only exception is the North East and Yorkshire where daily new cases continue to fall 

    • Age groups: cases in the over 60s are slightly up from last week, notably in Wales, which is a key metric linked to hospital admissions (see graph below)

    The ZOE COVID Symptom Study UK Infection Survey figures are based on around one million weekly reporters and the proportion of newly symptomatic users who have positive swab tests. The latest survey figures were based on data from 10,442 swab tests done between 29 November to 13 December 2020. 

    ZOE COVID Symptom Study English Tier Dashboard 

    With the recent Tier change announcements, the ZOE COVID Symptom Study’s English Tier Dashboard [**] this week shows the regions that are performing badly in Tier 2 and well in Tier 3. Full table of results below. 

    Tim Spector OBE, lead scientist on the ZOE COVID Symptom Study app and Professor of Genetic Epidemiology at King’s College London, comments on the latest data:

    With just a week until Christmas Day it’s a bleak picture across the UK, particularly for Wales and London. Our data shows that cases and hospitalisations are rising again, which worryingly could mean the start of a third wave earlier than we expected. Sadly, Christmas 2020 won’t be normal . People should stay in small groups, avoid travelling to and from higher risk areas and socialise outdoors. People also need to know about the 20+ symptoms of early infection they can experience including fatigue and headache and not take risks if they start feeling unwell. There are no exceptions, everyone needs to take care, but we are urging people to consider postponing Christmas socialising until Easter.”

    Graphs and tables for ZOE COVID Symptom Study - 18th December 2020:

    Worst performing regions in Tier 2:

    Best performing regions in Tier 3:

    Incidence / Daily new symptomatic cases regional breakdown [*]

    Borough-level Prevalence map of London

    Borough-level prevalence rates in London

    The COVID Symptom Study UK Infection Survey results over time for the UK

    Table of R Values

    Map of UK prevalence figures: 

    Estimated rate of people with Symptomatic COVID across age groups


    [*] Note that incidence estimates by NHS region are calculated separately from the UK nations and  they don’t necessarily add up to the total for England.

    [**] Explanation of how the English Tier Dashboard is created. Using data from the app and from publicly available sources, the ZOE app team has created a way of tracking regions based on alignment with the five key indicators the Government has outlined as its criteria for the current tiers in England (five indicators detailed below). Based on this data, the English Tier Dashboard ranks the regions to show which areas best and worst according to the government’s own criteria. Note that prevalence rates indicate the total numbers with symptoms and typically lag the changes in daily new symptomatic cases (incidence). 

    Government indicators are: 

    Sources to recreate the government indicators:

    CSS data:

    • Prevalence and prevalence rate in the 60+ age group is computed  on the tier subregion level.

    • Positivity rate and R is computed  on NHS region level.

    Publicly available NHS data:

    • The % hospital bed occupancy is calculated as a ratio of the Total number of confirmed COVID-19 patients in hospital on the reporting date (source: coronavirus.gov.uk, frequency: daily) and the overnight bed availability for acute and general cases (source: NHS Statistics, frequency: quarterly)


    This analysis for incidence data requires swab testing, which was kindly provided by the Department of Health and Social Care for England. As Scotland and Wales are not yet offering tests to our app users, we provided indirect estimates using countrywide averages and wide confidence limits. Testing is happening in Northern Ireland, but the number of participants is too few to generate an accurate estimate. These figures exclude care homes as there is not enough data from the app to estimate this population.


    The COVID Symptom Study UK Infection Survey has been running since early May when the COVID Symptom Study commenced the daily swab testing programme provided by the Test and Trace. The CSS has so far recorded over a million swab results from app users. The COVID Symptom Study UK Infection Survey estimates the number of current COVID-19 positive cases in the community based on the information logged by users in the app and the results from the swab testing programme. It identifies differences in numbers within the regions throughout the UK, and tracks the change in estimated cases over time. It is the largest survey of its kind in the UK. We estimate from a sub-study of app users with antibodies that the asymptomatic rate is around 19%, which should be added when comparing to general surveys like ONS. The paper is live on the Journal of Infection: https://www.journalofinfection.com/article/S0163-4453(20)30653-8/fulltext