Coronavirus live news: US confirms 1m cases in a week; Boris Johnson self-isolating
UK PM has no symptoms but has been confirmed as contact of positive case; Global cases rise by 4m in one week; Japan emerges from recession
- Boris Johnson told to isolate after contact with Covid-positive MP
- Covid vaccine hopes must not make Britons complacent, warns adviser
- Covid vaccine rally fuels market optimism of a faster global recovery