Portrait of the week: Vaccine hopes up, Zoom shares down and Biden calls Boris
Home Pfizer and BioNTech announced a vaccine against Covid-19 of 90 per cent efficacy from two injections three weeks apart. It was not known if it prevented transmission of the virus. The vaccine has to be stored at an ultra-low temperature of minus 80˚C. In July, the British government had bought 40 million doses, enough