Travel from South Africa into the US is now banned, with the exception of returning US citizens.

Travellers who are not US citizens, who have been in South Africa, Brazil, the UK and Ireland, and 26 European countries that allow travel across open borders, make up a list of those not allowed into the US, with effect from midnight on January 30.

It seems likely that returning US citizens will be required to present a negative COVID-19 test certificate prior to departure and observe a self-isolation period following entry into the country.

The US Centers for Disease Control and Prevention (CDC) has also said that shortly, all people will have to wear masks on aircraft, ferries, trains, subways, buses, taxis, and ride-share vehicles.

Reports say the CDC will not consider granting temporary waivers to airlines to exempt some travellers from countries with limited testing capacity, as had been requested by some US airlines last week. CDC officials said they would consider case-by-case humanitarian exemptions for some travellers if needed.

The travel ban from South Africa, the UK and Brazil appears to be because of concerns about new variants of the COVID-19 virus, some of which have made their way into Europe and have been the cause of a slew of bans by European countries on travellers who have visited or transited through South Africa, UK or Brazil. The still-unknown qualities of the variants mean that there are fears that the available vaccines do not give cover for variant infections.

The US, which has seen over 25m cases under the Trump administration, has tightened COVID-19 controls as the first order of business under President Biden.