Health officials warn Americans not to let their guard down

People wait at a Covid-19 testing site in North Hollywood, Los Angeles (Richard Vogel/AP)

Top health officials in the US have warned Americans that with a Covid-19 vaccine perhaps just days away, and with most of California heading into another lockdown because of a surging outbreak, this is no time to let their guard down.

Dr Deborah Birx, the White House coronavirus response co-ordinator, said on NBC’s Meet The Press: “The vaccine’s critical.