The head of the World Health Organization’s Europe office said Tuesday that health officials are turning their attention to growing rates of COVID-19 infection in Eastern Europe, where six countries — including Russia and Ukraine — have seen a doubling in case counts over the last two weeks.

Dr. Hans Kluge said the 53-country region, which stretches to former Soviet republics into central Asia, has now tallied more than 165 million confirmed coronavirus cases and 1.8 million deaths linked to the pandemic — including 25,000 in the last week alone.

“Today, our focus is towards the east of the WHO European region,” Kluge said in Russian at a media briefing, pointing to a surge in the highly transmissible omicron variant. “Over the past two weeks, cases of COVID-19 have more than doubled in six countries in this part of the region (Armenia, Azerbaijan, Belarus, Georgia, the Russian Federation, and Ukraine).”

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“As anticipated, the omicron wave is moving east: 10 eastern Member States have now detected this variant,” he said.

Omicron, however, is milder than previous variants and health care systems in most countries around the world aren’t under strain.

Kluge sought to put an emphasis on improving vaccination rates, which have lagged in Eastern Europe compared to the rest of the region. He said less than 40% of people over age 60 in Bosnia, Bulgaria, Kyrgyzstan, Ukraine and Uzbekistan have completed a full COVID-19 vaccine series.

He called on governments and health officials “to closely examine the local reasons influencing lower vaccine demand and acceptance, and devise tailored interventions to increase vaccination rates urgently, based on the context-specific evidence.” He also said it was “not the moment to lift measures that we know work in reducing the spread of COVID-19.”

The WHO Europe chief also highlighted his “message of hope” — pointing to high levels of immunity through vaccination or recovery from infection, and the looming end of the winter season that causes many people to gather indoors, where the virus can spread more easily.

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