Covid-19 cases in the UK have increased for the first time in a week, as the Health Secretary warned “no-one really knows” what will happen next with the numbers. Sajid Javid followed Prime Minister Boris Johnson in adopting a cautious tone after official figures had shown the number of newly reported cases dropped for seven days in a row. Mr Javid, who has previously warned there could be 100,000 daily coronavirus cases over the summer, said he hoped recent falls in the numbers would be sustained but it was important not to be “too optimistic”.