Francois Balloux

Francois Balloux is professor of computational systems biology and director of the UCL Genetics Institute

Why China can’t stop zero Covid

From our UK edition

The Covid situation in China is not looking good right now. The authorities have trapped themselves into a situation from which there's no obvious escape strategy. Whatever they choose – or will be forced – to do next will be very costly. The country is extremely poorly prepared for a major surge of the virus So far China has only managed to suppress Covid with brutal restrictions. Those are becoming increasingly untenable and the population is suffering. Unrest is spilling out into the streets in cities across the country. A major surge seems largely inevitable in the short term unless the authorities choose to enforce even more ruthless measures. A major Covid wave in China would lead to a dramatic death toll.

Should we worry about the BA.2 Omicron variant?

From our UK edition

When the Omicron variant (now categorised as BA.1) swept across the world at the end of last year it was seen by optimists as the final chapter in the Covid story – it was so contagious it would infect essentially anyone, but would be far less likely to cause serious illness. Now a new wave of Omicron – the BA.2 variant – is becoming dominant in many parts of the world. In the UK, cases are again on the rise. Genomic surveys show that BA.2 made up 76 per cent of new cases in England as of 5 March. The below is from the Sanger Institute: So what's going on? Firstly, both the BA.1 and BA.2 variants do not have an intrinsically much higher growth rate than any previous variant. Instead, they have spread globally for two main reasons.