The chief of the World Health Organization (WHO) Tedros Adhanom Ghebreyesus warned Tuesday that some nations issued blanket measures against the omicron COVID-19 variant that may not be necessary and penalized African nations unfairly.

"I well understand the concern of all countries to protect their citizens against a variant that we don't yet fully understand," said Tedros.

"But I am equally concerned that several Member States are introducing blunt, blanket measures that are not evidence-based or effective on their own, and which will only worsen inequities."

First reported in southern Africa a week ago, the variant has brought global alarm, led to travel bans and highlighted the disparity between massive vaccination pushes in rich nations and sparse inoculation in the developing world.

In remarks to a closed-door meeting posted on its website, the WHO's Ethiopian head urged the 194 member states to stick to "rational, proportional" measures.

There were still more questions than answers, Tedros said, about omicron's severity and the effectiveness of vaccines.

No omicron-linked deaths have yet been reported though the WHO has said it poses a high risk of infection surges.

"Once again, I thank Botswana and South Africa for detecting, sequencing and reporting this variant so rapidly," added Tedros. "It is deeply concerning to me that those countries are now being penalized by others for doing the right thing."

'Knee-jerk reaction'
Mid-way through a three-day WHO meeting of health ministers, Namibia's delegation on Tuesday expressed disappointment towards those states imposing travel bans on southern Africa.

"This travel ban is a knee-jerk reaction grounded in politics, not in science or guidance from the WHO Constitution," it said. "We therefore ask why is it that other states that (detected) the variant in persons who have no travel history to southern Africa are exempted from this travel ban"

Tanzania called for an immediate lifting of the travel curbs, which are hurting tourism in the region, while Canada voiced gratitude for regional transparency.

"Transparent international collaboration, as demonstrated by the leadership of South Africa and the South African scientists who swiftly and openly shared information on this new variant, is what is needed now more than ever," said Leslie Norton, Canada's U.N. ambassador in Geneva.

"Through your actions you bought the world time."

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