Omicron will likely outpace Delta: WHO to member nations

Aditi Tandon

CT News Service

New Delhi, December 13

The World health Organisation in its first technical brief on Omicron to member nations has said the variant of concern will likely outpace Delta, currently the dominant variant globally.

The world body also said Omicron could be detected with existing tests and current treatment strategies would work.

In the technical brief and priority actions for member countries titled “Enhancing Readiness for Omicron (B.1.1.529)”, the WHO said that based on current limited evidence, Omicron appeared to have a growth advantage over Delta.

“It is spreading faster than the Delta variant in South Africa where Delta circulation was low, but also appears to spread more quickly than the Delta variant in other countries where the incidence of Delta is high, such as in the United Kingdom. Whether Omicron’s observed rapid growth rate in countries with high levels of population immunity is related to immune evasion, intrinsic increased transmissibility, or a combination of both remains uncertain. However, given the current available data, it is likely that Omicron will outpace the Delta variant where community transmission occurs,” the global body said.

As of December 9, cases of human infections with Omicron have been identified in 63 countries across all six WHO regions with the spread picking up pace.

WHO also said more data were needed to understand the clinical severity of Omicron and preliminary findings from South Africa suggest it may be less severe than Delta.

All Omicron cases reported in the EU and the European Economic Area to date have been mild or asymptomatic.

On vaccine impact of the new variant the world body said there was limited available data and no peer-reviewed evidence on vaccine efficacy for Omicron. “There is some preliminary evidence that the incidence of reinfection has increased in South Africa, which may be associated with antibody-mediated immune evasion,” WHO said.

It added that the diagnostic accuracy of routinely used PCR and antigen-based tests did not appear to be influenced by Omicron and current therapeutic interventions are expected to remain effective.

“However, monoclonal antibodies will need to be tested individually, for their antigen binding and virus neutralization and these studies should be prioritized,” said the WHO which had declared Omicron a VOC on November 26.