Nature reports:

On 11 January, just seven weeks after the Omicron variant was first reported, the World Health Organization (WHO) warned of a “tidal wave” of infection washing from west to east across the world. Fifty of the 53 countries in Europe and central Asia had reported cases of Omicron, said Hans Henri Kluge, the WHO’s regional director for Europe.

Countries would have to cope as best they could, he said, guided by their individual epidemiological situation, available resources, vaccination-uptake status and socio-economic context. In recent weeks, countries in Europe and the United States have felt the full force of the Omicron wave; in the United Kingdom, which has reported most infections, daily COVID-19 cases peaked at more than 160,000 earlier this month. Scientists there say all nations are facing the same major problem: the sheer speed at which the variant spreads.

And although the WHO and others have suggested that huge numbers of omicron infections could signal the end of the pandemic, because of the short-term surge in immunity that will follow, researchers warn that the situation remains volatile and difficult to model.

“It moves so fast that it gives very little time to prepare any kind of response. So, decisions have to be made under huge uncertainty,” says Graham Medley, an infectious-diseases modeller at the London School of Hygiene & Tropical Medicine, who advises the UK government. [Continue reading…]