Updated 10th January 2022

What is the Omicron COVID-19 variant and what do we know so far?

Here’s what we know so far about Omicron, what you can do to help keep yourself and others safe, and how you can help with research into the new variant.

What’s the latest news on Omicron in the UK?

Regular updates ceased on Thursday 6th January 2022, as Omicron is now dominant in the UK. Stay up-to-date with the latest information on COVID-19 by logging your health each day in the ZOE COVID Study app.

Update: Thursday 6th January 2022

  • According to ZOE COVID Study incidence figures, there are more than 208,471 daily new infections in the UK. While we continue to break records day by day, growth in new cases has slowed down significantly. Check the daily report to learn more about the latest UK figures.

Daily COVID incidence on 3 Jan 2022
  • The slowdown is largely driven by a steep drop in case numbers in London, the UK region with the highest level of COVID cases. Cases continue to rise in all other regions.

Regional UK COVID Cases
  • Cases are slowing among the under 35 age groups but rising in all older age groups, including the vulnerable over 75s, who are at higher risk of hospitalisation as a result of COVID infection.

COVID infection in the UK by age group
  • Official Government figures for the prevalence of Omicron stopped on the 31st of December, and Omicron now accounts for over 96% of COVID-19 cases in England. As a result, our map will no longer be updated.

  • Our data now indicates that more than half of all 'colds' are likely to be positive COVID-19 infections.

COVID infection vs Cold-like illness
  • Omicron has reached total COVID dominance in the UK and as such, we'll no longer maintain these regular updates as an addtional source of information on the rapid outbreak of a new variant. Please keep logging in the app and visit our website to stay up to date with the latest data on the COVID-19 outbreak.

Update: Friday 31st December 2021

  • According to ZOE COVID Study incidence figures, there are more than 198,391 daily new infections in the UK. While we continue to break records day by day, there are signs of case numbers slowing. Check the daily report to learn more about the latest UK figures.

  • More than 90% of cases in England are now Omicron according to UKHSA data. See how widespread Omicron is in your region by looking at the map here.

  • 48% of colds are estimated to be COVID according to our data.

  • Growth of daily COVID cases is very high in the North West with a R value of 1.3.

  • Skin rashes are not necessarily indicative of the Omicron variant of COVID and rank 31 in our symptom list. They do remain one of many symptoms which may be associated with all COVID variants. Read more about the symptoms specific to Omicron here.

Update: Thursday 30 December 2021

  • According to ZOE COVID Study incidence figures there are more than 194,450 daily new infections in the UK. There are signs of a slow down.

Incidence 30 December
  • Looking more closely at the data this slow down is due to cases in London slowing, but cases in most other regions are still exponentially growing.

Prevalence by region
  • Cases are going down in the 0-35 age group and plateauing in the 35-55. They are still rising in the 55+ age group which is a worrying trend.

Age groups

Update: Wednesday 29 December 2021

  • According to ZOE COVID Study incidence figures there are more than 192,290 daily new infections in the UK. This is an all time high and we are breaking records everyday. Check the daily report to learn more about the latest UK figures.

Incidence 29.12
  • +90% cases in England are now Omicron according to UKHSA data. See our map here.

  • Our data suggests, lower hospitalisation % compared to Delta, but this is being offset by the far higher number of cases.

Update: Thursday 23 December 2021

  • According to our latest research, half of colds in the the UK will be Covid, and the news has been covered by the BBC.

  • According to ZOE COVID Study incidence figures, there are more than 151,000 daily new infections in the UK. Check out our data page.

  • +75% cases in England are now Omicron according to UKHSA data. See our map in here.

  • Lowest % of cases of Omicron are in the North East, but they are catching up! Check the daily report to learn more about the latest UK figures.

  • The ZOE team are taking a much needed break - we will be back to provide an update on Wednesday 29th December. Safe stay and keep logging so we can keep tracking COVID in near real time.

Update: Wednesday 22 December 2021

  • According to ZOE COVID Study incidence figures, in total there are currently 144,284 new daily symptomatic cases of COVID in the UK.I n the vaccinated population (at least two doses) there are currently 56,346 new daily symptomatic cases in the UK

Incidence by vaccination status 22 December
  • +70% cases in England are now Omicron according to UKHSA data. See our map in here.

  • The UK R value is estimated to be around 1.2 and regional R values are; England, 1.2, Wales, 1.0, Scotland, 1.1. 

  • The R value in London is 1.5.

  • Highest figures ever across many UK regions (London, South East, East of England, East Midlands, North West and Scotland). Check the daily report to learn more about the latest UK figures.

Prevalence by region 22 December
  • The government have updated its stay at home/ self isolation advice, reducing the number of days to just seven days, however the guidance still has yet to update the symptom list. For the symptoms of Omicron please read this blog. 

  • Loss of smell and fever are less prevalent in Omicron cases than in Delta cases

  • Early data from our contributors also suggests that illness might be less severe

Update: Tuesday 21 December 2021

  • ZOE Incidence figures continue breaking records with 137,000 daily new infections in the UK.

Incidence figures 21st December
  • These huge figures are mainly driven by infections in people aged between 18 to 55 years old, but we’re now seeing an uptick in people +55 years old, which could lead to an increase of hospitalisation in the coming weeks as this age group is in general more fragile.

Incidence Age Group 21st December
  • From the sample of 171 individuals who logged in the ZOE App that they had been notified by NHS test and trace as a suspected/confirmed Omicron, we see the same top 5 symptoms of Omicron reported last week. Thanks to the all 17,000 contributors for logging their Omicron status with us. 

  • Due to the huge numbers of Omicron now in the UK, NHS test and trace is not telling users of their Omicron status anymore.

  • Omicron prevalence across England and specially in London shows a slow down in the last few days. Check our updated map.

Omicron Prevalence 21st December
  • We’ve written a new blog on our latest research into the after effects of the Booster vaccine - read more here.

Update: Monday 20 December 2021

Here's the latest from the team:

  • The latest ZOE figures, we've hit new record of 130,000 daily new cases in the UK. 

UK Incidence 18 Dec
  • According to the ZOE data, new COVID cases are now rapidly increasing across all regions in England, Scotland. New COVID cases are not increasing not exponentially in Wales yet. See all the ZOE figures here

  • Omicron is now predominant (>50%) across all regions of England except the North East. Check our updated map

  • Over the last four days, we’ve seen the rates of newly sick contributors coming down across several regions. However, these rates are still 2-3.5 times higher than last June when we recorded the lowest rate of newly sick contributors (dashed line).

Newly Sick Contributors 20 December
  • Given this newly sick rate includes contributors getting newly sick with any disease, this does not necessarily mean the COVID infection rate is on a downward trend yet. However, this could indicate that people are changing their behaviour (e.g. school holidays, minimising social interaction before Christmas) and that overall, less people getting sick. 

Update: Friday 17 December 2021

Our data team has updated incidence calculations to help track the rapid spread of the Omicron COVID-19 variant. Our incidence estimates are now based on positive PCR & LFT results up to two days ago. Previously we relied on data up to four days ago, but as Omicron spreads faster than any previous variant of COVID, we've taken this action to give you the most up-to-date information available.

Here's the latest from the team:

  • According to ZOE figures, we've now surpassed the figure of 100,000 daily new cases of COVID-19.

Incidence of COVID-19 in the UK
  • New cases are growing exponentially, especially among those aged 18 - 35 and 35 - 55.

COVID019 incidence in the UK by age group
  • More than 80% of the cases in London are now Omicron and the variant is predominant (greater than 50% of sequenced positive test results) in five English regions: London, East of England, South East,  East Midlands, and the North West. Explore our map of all English regions.

  • The prevalence of Omicron cases is increasing across all regions.

Prevalence of Omicron in English regions

Updates won't continue over the weekend but we'll be back with more info on Monday.

Stay safe and keep logging.

Update: Thursday 16 December 2021

A unique asset of the ZOE COVID Study app is that we can look at symptom reports as the earliest indication of infections. Please see the graph below which shows the daily number of newly sick contributors in the UK over the last month. This includes people who present any new symptoms, who might be infected with COVID or have some other illness. You can see that London is demonstrating a big spike, which means that many people are falling sick in that region, out of which a majority are likely to be infected with the Omicron variant.

Graph showing the daily number of newly sick contributors

We can also exclusively share with you a map of current Omicron prevalence in the UK, based on data provided to us by UKHSA. Click here to access the map.

The Omicron variant is spreading fast. Currently there are more than 4,700 cases of Omicron in the UK and one person has already died with it. The true number of infections is likely to be far higher, with Health Secretary Sajid Javid predicting that up to 200,000 people might soon be catching Omicron every day.

We still don’t know for sure whether Omicron causes less severe illness than previous variants. The latest data from South Africa suggests that Omicron symptoms might be milder, but it’s not yet clear whether that’s because it makes people less sick or whether there are high levels of pre-existing immunity in the population there.

The UK Health Security Agency is warning that two vaccine doses may not be enough to protect against Omicron, but adding a third booster dose provides much better protection

Booster jabs are being rolled out for all adults in the UK from this week - get boosted now to make sure you’re protecting yourself and others around you as we head into Christmas.

We’re gathering data through the ZOE COVID Study app to find out more about the symptoms and severity of Omicron, track its spread through the UK, and measure the effectiveness of vaccines and boosters against the new variant. As always, we’ll be sharing our findings with you as soon as we have enough data to start analyzing.

You can now report if you have a confirmed case of Omicron in the ZOE COVID app. 
If you’re not already a regular contributor, download the ZOE COVID app today to start logging your tests, vaccines, and daily health reports and contribute to this crucial research.

Update: Wednesday 8 December 2021

Multiple cases of Omicron infection have now been identified in many countries around the world, including hundreds in the UK, and the true figure is likely to be far higher. 

Many of these cases have no connection to travellers from places where the variant was first identified, suggesting that Omicron is already passing between people in the community - although exactly how much more transmissible it is than other variants such as Delta remains to be seen.

In the UK, 30% of UK PCR tests will report probable Omicron and will be confirmed by genomic sequencing a few days afterwards. The remainder will not be picked up by the PCR test but a sample will be examined by the government. 

Anyone confirmed positive will be contacted by local health protection teams and advised to self-isolate. Their close contacts will also be contacted by NHS Test & Trace and must also self-isolate, even if they have been fully vaccinated. 

People who are possibly infected with the Omicron variant will also be contacted by text or email. This guidance may change over time, and we’ll keep you updated as the situation develops. 

Right now, we still don’t have enough information to know whether the Omicron variant causes more severe COVID symptoms and who is most likely to get ill, or to what extent it can overcome immunity from vaccination or previous infections. 


While early reports from South Africa suggest that COVID symptoms caused by Omicron are relatively mild, we can’t directly transpose this to other populations with a different mix of ages, health and genetic backgrounds.

What are COVID variants?

SAR-CoV-2, the virus that causes COVID-19, is little more than a length of genetic code (RNA) wrapped in a spiky molecular coat.

When the virus infects someone, it copies itself and spreads out into the world in search of new hosts. Viral replication is quick and messy, so every time the virus is copied, there is the potential for mistakes to arise in its genetic code. 

Most of the time, these alterations — known as mutations — are small and irrelevant, or they put the virus at a disadvantage. 

Since COVID-19 was first identified in 2019, scientists have identified thousands of SARS-CoV-2 variants, most of which we haven’t heard about because they don’t affect the behavior of the virus or our defenses against it.

However, some mutations can make the virus more infectious or harmful, or enable it to evade the immune protection provided by vaccination or a previous infection. These variants, with names from the Greek alphabet, are designated as “variants of interest” or “variants of concern” (VoC) by the World Health Organization (WHO).

Read more about variants on our blog.

What is the Omicron variant?

The Omicron variant — or B.1.1.529, which is its scientific name — is a specific version of the SARS-CoV-2 virus. 

Omicron has been designated as a VoC by the WHO, meaning that it has the potential to have a significant impact on how easily the virus passes between people or how sick it makes them, as well as its potential to evade current tests, vaccines, treatments, or other protective measures.

Where did Omicron come from and where is it now?

Researchers all over the world are carrying out genomic surveillance, analyzing the genetic code of virus samples to look for new variants.

Scientists in southern Africa were the first to identify the new Omicron variant, with cases reported in South Africa and Botswana. 

However, this doesn’t mean that the variant actually arose there, only that this was the area where it was first detected. We don’t know exactly where the first case of Omicron emerged, who had it, or how they came to be infected with it — and it’s likely we’ll never know for sure. 

Reports of Omicron quickly followed from other countries, including Hong Kong, Belgium, Israel and the U.K., suggesting that the variant had already started to spread some time before it was spotted. 

As of December 1, 2021, Omicron has been found in 25 countries, and it’s likely that it will turn up in more.  

What's different about the Omicron variant?

Compared with other variants, such as the predominant Delta variant, Omicron has a relatively large number of mutations, many of which haven’t been seen before in other variants.

For example, there are more than 30 mutations in the genetic code for the spike protein on the surface of the virus, which could have big implications for how the variant spreads and how effective vaccines are against it.

However, while the large number of mutations is concerning, it’s not clear right now exactly how they influence the behavior of the virus or our immune response to it. 

Researchers are hard at work trying to figure out how all these mutations might affect the transmission of the virus and whether it can infect people who have been vaccinated or previously infected with a different variant.

Read more about the mutations in Omicron and what they mean.

Is Omicron more transmissible than Delta?

There are concerns that Omicron is spreading more quickly than Delta. It’s quickly become the dominant strain in South Africa, where it was first detected, and has spread to at least 38 countries.

This is where your daily reporting in the ZOE COVID Study app can help. In the U.K., positive PCR tests will be sequenced to identify the variant. In most cases, infected people with a positive PCR test result will be informed if they picked up Omicron, Delta, or another variant. 

We’re launching the ability to add this information to your positive test results so that we can help map the symptom profile and spread of Omicron.

Does Omicron cause worse COVID-19 symptoms?

It’s not clear at the moment whether Omicron makes people more sick than other variants, such as Delta. 

The South African doctor who first spotted the new variant in patients has said that the people she’s seeing with COVID-19 caused by Omicron are only mildly affected

But there are also reports that the number of hospitalizations in South Africa, which has a relatively high number of Omicron cases and low levels of vaccination, have increased significantly since the beginning of November. 

We will have to wait for more data to know whether Omicron causes more serious COVID symptoms than other variants and who is most at risk. But by reporting your symptoms daily and logging your health in the ZOE COVID Study app, we can keep you up to date with all the latest COVID symptoms, even if official guidance is out of date. 

How will I know if I have Omicron and what should I do?

You can’t tell if you have Omicron from a lateral flow test, only from a PCR. So if you test positive on a lateral flow or are experiencing COVID symptoms, you should get a PCR test as soon as possible.

In the UK, around a third of UK PCR tests are capable of detecting a probable case of Omicron, which will be confirmed by genomic sequencing a few days afterward. The remainder will not be picked up by the PCR test but a number of these other tests will be sequenced by the government to check for Omicron. 

Anyone confirmed positive will be contacted by local health protection teams and advised to self-isolate. Their close contacts will also be contacted by NHS Test & Trace and must also self-isolate, even if they have been fully vaccinated. 

People who are possibly infected with the Omicron variant will also be contacted by text or email. This guidance may change over time, and we’ll keep you updated as the situation develops. 

Do vaccines protect against Omicron?

This is the really big question, and it’s one we don’t have an answer for yet. 

The current COVID vaccines work by training the immune system to recognize the spike protein on the surface of the virus, leading to the production of protective antibodies and T-cells. 

If the spike protein in a new variant is different enough from the spike used to design the vaccine, then there’s a chance that the level of protection will not be so good. 

Researchers are carrying out lab experiments to test whether antibodies produced in response to vaccination can still recognize and protect against the Omicron variant. But the immune system is complex, so these tests can’t give the full picture on the level of protection from the current vaccines.

The real test will be in the real world, tracking how many people who have been vaccinated and/or previously infected with other COVID variants can get infected again, and how seriously ill they become. This is why your reports in the ZOE COVID Study app are crucial.

In the longer term, it may be necessary to make booster vaccines based on Omicron. Other researchers are working on universal, future-proof vaccines that can cope with any future variants that might emerge.

Do COVID tests work with Omicron?

We know that PCR tests can detect the Omicron variant. In fact, Omicron causes a result known as “S-gene dropout” in some types of PCR test, which isn’t seen with Delta, making it a useful way of tracking the spread of the new variant.

Based on initial reports, it looks like lateral flow tests can also detect infection with the Omicron variant. 

If you feel unwell with any of the most common COVID symptoms — including a runny nose, headache, sneezing, sore throat, persistent cough, fever, or loss of taste or smell — you should get a PCR test.

Know the symptoms of COVID-19.

How can I avoid catching Omicron?

Although we don’t yet have definitive data on how well the current vaccines protect against the Omicron variant, it’s likely that they will offer at least some level of protection. It’s also important to remember that the vaccines work well against the other variants of the virus that are still out there, including Delta.

The best way to protect yourself and others from Omicron or any other variant is to get fully vaccinated, which we now consider to be three vaccine doses, even if you’ve already had COVID-19.

It’s also important to take sensible precautions such as wearing a mask in public, being careful in crowded places, and ensuring good ventilation indoors.

Not only does this cut your chances of catching the virus and becoming seriously ill, it also reduces the likelihood of passing it on to others who may be more vulnerable.

How can I help with research into Omicron?

There are many things we still don’t know about the new Omicron variant, and there will be more information emerging over the coming weeks as researchers gather data and carry out experiments.

We urgently need to gather more information about the symptoms of Omicron and how it’s spreading, and to find out whether people who have been vaccinated or previously infected can catch it again.

You can help by downloading the ZOE app and logging daily health reports, as well as tests and vaccines. It only takes a minute, but you’ll be contributing to vital research to help us build a clearer picture of what’s going on.

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