On 26 November, WHO’s Technical Advisory Group on SARS-CoV-2 Virus Evolution (TAG-VE) designated the B.1.1.529 variant, first reported by South Africa 2 days earlier, as a variant of concern, named Omicron.
Key things to know
The more COVID-19 circulates, the more opportunities the virus has to change, and the more new mutations we can expect to see; Delta and Omicron are examples of that.
Omicron is a variant of concern because it has dozens of mutations that can affect the way it behaves. Due to this mutation profile, it needs to be further investigated for its potential impacts.
While we wait to learn more about Omicron, Delta dominates transmission in the WHO European Region, and responding to it should remain our priority at this stage.
Current vaccines offer protection against severe disease and death from all COVID-19 variants, including Delta and Omicron.
The most important thing people can do is to stop the virus at its source by completing their vaccine series as soon as possible and continuing to protect themselves with all other proven preventive measures.
We spoke to Dr Richard Pebody, who leads the High-threat Pathogen team and the Surveillance and Laboratory pillar of the COVID-19 Incident Support Management Team (IMST) at WHO/Europe to find out more about the variant, why it is of concern and what can be done to control it.
Why is Omicron a variant of concern?
All viruses, including the COVID-19 virus, change over time and this is a natural phenomenon. However, some mutations or combinations of mutations may change the way the virus behaves. Omicron is of concern because it has a large number of mutations, some of which have been associated with potential increased transmissibility and possible immune escape – by this we mean, there is a chance people may get infected by it even if they have developed some natural immunity from previous COVID-19 infection, or following COVID-19 vaccination. At the same time, there are mutations that have never been documented before. Because of this, the Omicron variant needs to be investigated for us to have a better understanding of its potential impacts.
When does WHO designate a variant of concern?
WHO will designate a variant of concern when the virus in question has been demonstrated to be associated with 1 or more of the following changes, at a degree of global public health significance:
- an increase in transmissibility or detrimental change in COVID-19 epidemiology;
- an increase in virulence or change in clinical disease presentation;
- a decrease in effectiveness of public health and social measures or available diagnostics, vaccines and therapeutics.
What do we know about the variant at the moment?
What we know is that the variant has been spreading quite quickly in one province of South Africa and cases have also been reported in other parts of the world, including in the European Region. We are likely to see more Omicron cases being reported by countries over the days and weeks to come, as countries begin to look for it more.
We are being cautious, by calling attention to this new variant of concern, but need to take the time to see how it plays out in the world. WHO is joining hands with researchers in South Africa and around the world who are conducting studies to better understand many aspects of Omicron, and will continue to share the findings of these studies as they become available.
At the same time, we must not forget that we are already dealing with a highly transmissible variant – the Delta variant – which accounts for almost all cases in our region. Preventing the transmission of Delta should remain our priority at this stage.
What is your overall message to people and governments in our region?
As mentioned, it is the Delta variant that is dominating transmission in the European Region and responding to it should be our priority right now. Available preventive measures, including vaccination, are proven to be effective against all current COVID-19 variants.
Currently, the European Region is the epicentre of the pandemic. Recently, the Region was responsible for over 2 thirds of global cases and deaths. Cases and deaths have doubled in the Region over the last 2 months and this is putting quite a bit of pressure on our health systems.
The more COVID-19 circulates, the more opportunities the virus has to mutate – the Delta and Omicron variants are good examples of this. Thus, it is essential that we all stop the circulation of the virus at its source.
What can we do as individuals to stop the virus circulating?
There is a range of proven measures that we should continue taking to protect ourselves against COVID-19 and all its variants, namely:
- Getting vaccinated to be protected from severe illness and death – a new study estimates that 470 000 lives have been saved among those aged 60 years and over since the start of COVID-19 vaccination rollout in 33 countries across the European Region. Vaccines also reduce virus circulation, reducing the chances for a new mutation that could hit us harder. We need more people to be vaccinated, everywhere.
- Combining vaccination with other protective measures as a matter of routine to further reduce our risk of exposure and prevent ourselves from passing the virus on to others – including:
- wearing a well-fitting mask
- maintaining physical distance of at least 1 meter
- improving ventilation of indoor spaces
- avoiding crowded, confined and closed settings
- regularly cleaning hands
- coughing or sneezing into a bent elbow or tissue.
As we are approaching the festive season, what do you recommend to people around the Region in view of this new variant?
Winter holidays are a time for family, community and renewal, and this is the second year that we are called to exercise high caution. Indoor gatherings, even smaller ones, can give the virus a ground to thrive. Gatherings and celebrations should be held outside if possible, and participants should wear masks and maintain physical distancing. If held indoors, limiting group size and ensuring good ventilation to reduce exposure risk are key. This can be done by opening a door or window when safe to do so.
All preventive measures that work against the Delta variant continue to be effective against Omicron, based on data so far. Getting vaccinated with complete doses and taking all other preventive measures will minimize the risk of infection.
What can governments and authorities do?
WHO recommends that the countries of the Region accelerate vaccination against COVID-19 and intensify preventive measures to suppress transmission of all variants. This includes:
- continuing to vaccinate, targeting those most at risk, including with booster doses for eligible groups;
- increasing adherence of all individuals to protective measures;
- putting in place social measures to prevent crowding and people gathering in confined spaces;
- activating and prioritizing case investigation and contact tracing for any COVID-19 cases, including Omicron;
- enhancing testing (and sequencing) and making it available freely to people with symptoms;
- identifying surge capacity in health systems.
In addition, they should report cases and clusters of COVID-19 and its variants to WHO and the European Centre for Disease Prevention and Control (ECDC) in a timely manner, to ensure we have an up-to-date picture and responses can be effective.
Lockdowns should only be used as a last resort as they are very costly measures, and if a government decides to implement such stringent restrictions, they should be as targeted as possible with the time used to build up public health capacities.
What travel advice would you give to individuals in relation to the emergence of Omicron?
Policies regarding travel restrictions are national decisions and each country needs to conduct a risk–benefit analysis when implementing travel measures.
People who are unwell, who have not been fully vaccinated, or do not have proof of previous infection and are at increased risk of severe COVID-19, including people 60 years of age or older and those with comorbidities (such as heart disease, cancer and diabetes) are advised to postpone travel to areas with community transmission. All travellers are reminded to remain vigilant for signs and symptoms of COVID-19, to get vaccinated when it is their turn and to adhere to preventive measures at all times, regardless of their vaccination status.
Essential international travel, including travel for emergency and humanitarian missions, travel of essential personnel, repatriations and cargo transport of essential supplies should continue to be prioritized at all times during the COVID-19 pandemic.
What is WHO doing in response to Omicron?
WHO is working with countries and partners to understand the potential impact of this variant on our existing preventive measures, including vaccines. Studies are ongoing in laboratories looking at how the existing COVID-19 vaccines can perform against the variant. But we are also looking at the epidemiology and at the vaccination status of people who are infected with the Omicron variant.
Here in the European Region, we have rapidly set up a dedicated team within IMST to respond to the emerging challenge of Omicron. This team will:
- identify implications for the European Region
- adjust recommendations to potential scenarios
- collect data from Member States on cases of B.1.1.529 (Omicron)
- develop key messages for public communications.
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