It was 26 November 2021 that WHO declared that the world was going through a brand new variant of concern: Omicron. It could go on to alter the trajectory of the COVID-19 pandemic.
Rising proof was rapidly 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).
Consultants on the assembly fearful concerning the massive variety of mutations current on this variant, which differed significantly 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 had been coping with one thing new, one thing totally different, and one thing that the world needed to rapidly 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 labeled, employees rushed to tell and put together WHO places of work across the globe earlier than the information turned public. Photograph: WHO
The Omicron impact
Omicron was rapidly 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.
Nations which had thus far been profitable in retaining COVID-19 at bay via public well being and social measures now discovered themselves struggling. For people, the best value was paid by those that had been liable to extreme illness however not vaccinated, and we noticed hospitalizations and deaths rise in various locations world wide.
This graph exhibits reported COVID-19 instances in grey and deaths in blue; the affect of Omicron is obvious. Whereas Omicron was much less extreme in comparison with Delta, there have been nonetheless a big variety of deaths on account of this variant worldwide. The current decline in COVID-19 testing world wide has meant that we’re underestimating the true quantity instances, now greater than ever.
By March 2022, WHO and companions estimate that nearly 90% of the worldwide inhabitants had antibodies in opposition to the COVID-19 virus, whether or not via vaccination or an infection.
Total, although, this new variant triggered much less extreme illness than Delta on common. Scientists labored to know why this was so. A lot of elements doubtless performed a job. For instance, the virus replicated extra effectively within the higher airway, and inhabitants immunity had been steadily growing worldwide on account of vaccination and infections.
Whereas vaccines lowered the affect of Omicron, they themselves had been impacted: research have proven that vaccine effectiveness in opposition to an infection, illness, hospitalization and demise waned (although at totally different charges) over time. Nevertheless, safety in opposition to hospitalization and demise have remained excessive, stopping thousands and thousands of individuals from dying.
Well being employee and lengthy COVID affected person Nazibrola Bidzinashvili conducts a self-test for COVID-19 at dwelling in Tbilisi, Georgia. Georgia, like many different nations, noticed an enormous wave of Omicron infections, that peaked on the finish of January 2022. Photograph: WHO/Hedinn Halldorsson
The subsequent variant of concern?
Because the emergence of Omicron, the virus has continued to evolve. Right now, there are over 500 sublineages of this variant circulating, however not one has been designated as a brand new variant of concern.
To this point, these sublineages of Omicron have a lot in frequent: 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, they usually all have mutations that make them escape built-up immunity extra simply. Which means that they’re comparable of their affect on public well being, and the response that’s wanted to take care of them.
If the virus had been to alter considerably – like if a brand new variant triggered extra extreme illness, or if vaccines not prevented extreme illness and demise – the world would want 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. Nations like Singapore have performed an necessary position in monitoring the virus and sharing their findings with WHO and the bigger world neighborhood. Photograph: WHO/Blink Media – Juliana Tan
WHO, along with scientists and public well being professionals world wide, continues to watch the circulating variants for indicators of the following variant of concern. Nevertheless, there’s apprehension as a result of testing and sequencing are declining globally and the sequences which are out there aren’t globally consultant (most sequences are shared from high-income nations).
WHO and companions additionally stay involved that surveillance on the human-animal interface is proscribed, the place the following variant of concern may come from.
Whereas it could be tough to cease a brand new variant from rising,
fast detection and knowledge sharing means its affect on our lives
might 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-Common Dr Tedros visits the Centre for Epidemic Response & Innovation exterior of Cape City, South Africa. Scientists from the institute had been among the many first to share essential information on Omicron with WHO. Photograph: Twitter/@drtedros