Japan, India and Taiwan introduce measures to prevent influx of cases as experts say lack of data makes it difficult to assess risk

Virologists are watching nervously to see how China’s abrupt decision to drop some of its toughest Covid-19 restrictions, including scrapping quarantine rules for travellers, may affect variants and their global spread as some countries increase precautionary measures.

China’s decision on Monday to drop quarantine for overseas visitors from 8 January has prompted concerns about the potential for new variants to spread beyond China’s borders. Japan and India are among the countries that have introduced measures to prevent an influx of cases.

This article was amended on 28 December 2022. Airfinity estimates there are more than 5,000 deaths a day in China, rather than new cases as an earlier version said.