Omicron quickly overtaking Delta, efficacy of vaccines reduced: WHO - NewsBytes

The Omicron variant of coronavirus is rapidly displacing the Delta variant and reaching global dominance, said a senior official from the World Health Organization (WHO) on Tuesday.

Although it causes a less severe COVID-19, there is "increasing evidence" that Omicron can escape prior immunity, warned WHO's Infectious Disease Epidemiologist and COVID-19 Technical Lead Maria Van Kerkhove.

She said that Omicron is becoming the most common variant found in infected persons.

Since December, six studies have found evidence of lower vaccination efficacy of COVID-19 vaccines against the Omicron variant, the WHO update said.