500 Omicron strains evolved in one year of its emergence: WHO

And within hours, WHO declared this new variant a variant of concern. Speaking about the same, WHO release said, “We were dealing with something new, something different, and something that the world had to quickly prepare for. “

Within 4 weeks, as the Omicron wave travelled around the world, it replaced Delta as the dominant variant. It was also identified to be significantly more transmissible than Delta. 

By March 2022, WHO and partners estimate that almost 90% of the global population had antibodies against the COVID-19 virus, whether through vaccination or infection.

How the variant has evolved over the year? 

Since the emergence of Omicron, the virus has continued to evolve. Today, there are over 500 sublineages of this variant circulating, but not one has been designated as a new variant of concern.

Should we be worried about Omicron at this stage? 

So far, these sublineages of Omicron have much in common: they are all highly transmissible, replicate in the upper respiratory tract and they all have mutations that make them escape built-up immunity more easily, WHO notes and further adds, however, they tend to cause less severe disease compared to previous variants of concern.

This means that they are similar in their impact on public health, and the response that is needed to deal with them. 

Hence, even though there are over 500 sub-variants circulating, they are not as concerning as previous variants.

How the vaccines have helped?

 While vaccines reduced the impact of Omicron, they themselves were impacted: studies have shown that vaccine effectiveness against infection, disease, hospitalization and death waned (though at different rates) over time. However, protection against hospitalization and death have remained high, preventing millions of people from dying, WHO pointed out