Published on 10:28 PM, November 30, 2021

Covid-19 Omicron variant: WHO DG Tedros warns against 'overreaction'

World Health Organization chief Tedros Adhanom Ghebreyesus attends a ceremony to launch a multiyear partnership with Qatar on making FIFA Football World Cup 2022 and mega sporting events healthy and safe at the WHO headquarters, in Geneva, Switzerland, October 18, 2021. Fabrice Coffrini/ Pool via REUTERS

The head of the World Health Organization (WHO) voiced concern on Tuesday that some states are introducing blanket measures aimed at the Omicron coronavirus variant that he said were "not evidence-based or effective on their own" and were penalising southern African countries that reported the strain so quickly.

Tedros Adhanom Ghebreyesus, in a speech to the WHO's 194 member states, urged them to take "rational, proportional risk-reduction measures" in keeping with the agency's 2005 International Health Regulations.

"We still have more questions than answers about the effect of Omicron on transmission, severity of disease, and the effectiveness of tests, therapeutics and vaccines," Tedros said in remarksposted on the WHO website.