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 COVID-19 variants, including Delta. While evidence is still
emerging, we expect current vaccines should also protect against severe
disease from the Omicron variant.
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.
The content of this article was amended on 08 December 2021 to
clarify that while evidence is still emerging, we expect current
vaccines should protect against severe disease from the Omicron variant.