One yr because the emergence of COVID-19 virus variant Omicron

It was 26 November 2021 that WHO declared that the world was going through a brand new variant of concern: Omicron. It will go on to alter the trajectory of the COVID-19 pandemic.

Rising proof was shortly shared by scientists from Botswana, Hong Kong and South Africa and mentioned in a particular assembly of WHO’s Technical Advisory Group for Virus Evolution (TAG-VE).

Specialists on the assembly nervous in regards to the giant variety of mutations current on this variant, which differed drastically from the opposite variants that had been detected thus far. Early information confirmed Omicron’s fast unfold in some provinces in South Africa
and an elevated danger of reinfection in comparison with the beforehand circulating variants.

Simply hours later, WHO declared this new variant a variant of concern: we have been coping with one thing new, one thing totally different, and one thing that the world needed to shortly put together for.

 

WHO’s COVID-19 technical lead, Dr Maria Van Kerkhove, information a video asserting the classification of Omicron as variant of concern. As quickly because the variant was categorized, employees rushed to tell and put together WHO workplaces across the globe earlier than the information turned public. Photograph: WHO

 

The Omicron impact

Omicron was shortly recognized as being considerably extra transmissible than Delta, the previous variant of concern. Inside 4 weeks, because the Omicron wave travelled world wide, it changed Delta because the dominant variant.

International locations which had thus far been profitable in conserving COVID-19 at bay by way of public well being and social measures now discovered themselves struggling. For people, the best worth was paid by those that have been susceptible to extreme illness however not vaccinated,
and we noticed hospitalizations and deaths rise in plenty of locations world wide.

 

This graph reveals reported COVID-19 circumstances in grey and deaths in blue; the affect of Omicron is evident. Whereas Omicron was much less extreme in comparison with Delta, there have been nonetheless a big variety of deaths as a consequence of this variant worldwide. The current decline in COVID-19 testing world wide has meant that we’re underestimating the true quantity circumstances, now greater than ever.

 

By March 2022, WHO and companions estimate that just about 90% of the worldwide inhabitants had antibodies in opposition to the COVID-19 virus, whether or not by way of vaccination or an infection.

Total, although, this new variant precipitated much less extreme illness than Delta on common. Scientists labored to know why this was so. A variety of elements seemingly performed a task. For instance, the virus replicated extra effectively within the higher airway, and
inhabitants immunity had been steadily growing worldwide as a consequence of vaccination and infections.

Whereas vaccines lowered the affect of Omicron, they themselves have been impacted: research have proven that vaccine effectiveness in opposition to an infection, illness, hospitalization and loss of life waned (although at totally different charges) over time. Nonetheless, safety in opposition to hospitalization
and loss of life have remained excessive, stopping hundreds of thousands of individuals from dying.

 

Well being employee and lengthy COVID affected person Nazibrola Bidzinashvili appears by way of outcomes from current lab assessments at her dwelling in Tbilisi, Georgia. Georgia, like many different international locations, noticed an enormous wave of Omicron infections, that peaked on the finish of January 2022. Photograph: WHO/Hedinn Halldorsson

 

The following variant of concern?

Because the emergence of Omicron, the virus has continued to evolve. As we speak, there are over 500 sublineages of this variant circulating, however not one has been designated as a brand new variant of concern.

Up to now, these sublineages of Omicron have a lot in widespread: they’re all extremely transmissible, replicate within the higher respiratory tract and have a tendency to trigger much less extreme illness in comparison with earlier variants of concern, and so they all have mutations that make
them escape built-up immunity extra simply. Because of this they’re comparable of their affect on public well being, and the response that’s wanted to cope with them.

If the virus have been to alter considerably – like if a brand new variant precipitated extra extreme illness, or if vaccines now not prevented extreme illness and loss of life – the world would wish to rethink its response. In that case, we might have a brand new
variant of concern, and with it, new suggestions and technique from WHO.

 

A lab employee prepares samples on the Nationwide Public Well being Laboratory in Singapore, a part of the community of WHO reference labs for COVID-19. International locations like Singapore have performed an vital function in monitoring the virus and sharing their findings with WHO and the bigger international group. Photograph: WHO/Blink Media – Juliana Tan

 

WHO, along with scientists and public well being professionals world wide, continues to observe the circulating variants for indicators of the subsequent variant of concern. Nonetheless, there’s apprehension as a result of testing and sequencing are declining globally
and the sequences which can be accessible aren’t globally consultant (most sequences are shared from high-income international locations).

WHO and companions additionally stay involved that surveillance on the human-animal interface is proscribed, the place the subsequent variant of concern might come from.

Whereas it is perhaps tough to cease a brand new variant from rising, fast detection and data sharing imply its affect on our lives could be minimized.

WHO stays grateful to public
well being professionals world wide for his or her continued surveillance
of the COVID-19 virus and the sharing of sequences and analyses.

WHO Director-Basic Dr Tedros visits the Centre for Epidemic Response & Innovation outdoors of Cape City, South Africa. Scientists from the institute have been among the many first to share essential information on Omicron with WHO. Photograph: Twitter/@drtedros