The Omicron variant of COVID-19 is on track to infect more than half of Europeans, but it should not yet be seen as a flu-like endemic illness, the World Health Organization (WHO) said on Tuesday.

Europe saw more than 7 million newly-reported cases in the first week of 2022, more than doubling over a two-week period, WHO’s Europe director Hans Kluge told a news briefing.

“At this rate, the Institute for Health Metrics and Evaluation forecasts that more than 50% of the population in the region will be infected with Omicron in the next 6-8 weeks,” Kluge said, referring to a research centre at the University of Washington.

Fifty out of 53 countries in Europe and central Asia have logged cases of the more infectious variant, Kluge said.

Evidence, however, is emerging that Omicron is affecting the upper respiratory tract more than the lungs, causing milder symptoms than previous variants.

But the WHO has cautioned more studies are still needed to prove this.