In a statement on Wednesday, the World Health Organization said, preliminary evidence indicates that COVID-19 vaccines may be less effective against transmission and infection from the Omicron variant of the coronavirus; it also carries a higher risk of reinfection.
As part of its weekly epidemiological update the WHO said, more data was required to better understand to what extent the Omicron may evade immunity derived from either vaccines or previous infection.
“As a result of this, the overall risk related to the new variant of concern Omicron remains very high,” said WHO.
The WHO has classified the Omicron variant as one of concern in April; it also reported that the percentage of Delta sequences registered on the GISAID global science database has declined this week compared with other variants of concern.
“This needs to be interpreted with caution as countries may perform targeted sequencing for Omicron and therefore upload fewer sequences on all other variants, including Delta,” said WHO.
The Delta variant continues to be dominant accounting for 99.2% of the 880,000 sequences uploaded to GISAID.
This trend is however on a downward slope midst the emergence of the Omicron variant. Out of the total, some 3,755, equivalent to 0.4%, were Omicron and the other three variants of concern together numbered 401, less than 0.1% each.