The longer Beijing enforces curbs on work and travel, the greater the global economic shock

The workshop of the world is closed. China is on a total-war footing. The Communist Party has evoked the "spirit of 1937" and mobilised all the instruments of its totalitarian surveillance system to fight both coronavirus, and the truth. Make GDP forecasts if you dare.

As of this week two-thirds of the Chinese economy remains shut. More than 80pc of its manufacturing industry is closed, rising to 90pc for exporters.

The Chinese economy is 17pc of the world economy and deeply integrated into international supply chains. It was just 4.5pc of world GDP during the SARS epidemic 2003, which some like to use as a reassuring template. You cannot shut down China for long these days without shutting down the world.

Wednesday's investor euphoria at reports of two new wonder drugs from Zhejiang University show how badly unhinged the market has become. This is not the way that medical science advances. Nor could these anti-virals possibly be ready, in time and at scale, to avert serious economic upheaval.

The open question is whether the coronavirus shock is enough to abort the fragile economic recovery underway since last summer’s near miss, when frightened central bankers in the US, Europe and 47 other jurisdictions cut rates in a drastic monetary U-turn.