Since first being recorded late last year in China, the Covid-19 coronavirus has spread around the world, and been declared a pandemic by the World Health Organization. However, differences in testing mean that the number of cases may be understated for some countries. The number of deaths is a more dependable indicator. The disease has hit certain countries, including Italy, Spain and the US, with particular cruelty. Meanwhile in Asia, where the disease began, the spread continues, although in China it seems for now to have passed its peak. Due to the unprecedented and ongoing nature of the coronavirus outbreak, this article is being regularly updated to ensure that it reflects the current situation at the date of publication. Any significant corrections made to this or previous versions of the article will continue to be footnoted in line with Guardian editorial policy.