Why has the UK decided to shut down its borders? The fear over new virus strains.
In the US, the Biden administration expects that a new, faster-spreading variant will become dominant by March and that half a million people would have died from the virus by the end of February.
A new very fast-spreading variant is currently crippling Brazil. Their health system is overwhelmed and doctors warn it is close to collapse.
More than 205,000 people in Brazil have already lost their lives.
Manaus, a city of more than two million people, lies in the heart of the remote Amazon rainforest. It was one the places worst hit during the first wave of the pandemic and is now suffering again. Dani Isdale reports.