Mercedes say Lewis Hamilton’s health is “improving” – but still do not know whether he will be able to race in the year’s final grand prix this weekend.

The world champion missed the Sakhir Grand Prix in Bahrain last weekend after contracting coronavirus.

Hamilton remains in isolation and must return a negative test result before he is allowed to travel to Abu Dhabi.

George Russell is in line to replace Hamilton if he cannot race.

The 22-year-old Williams driver starred on his Mercedes debut in Bahrain and was prevented from winning only by a pit-stop mix-up and then a puncture.