Experts working with the World Health Organisation (WHO) developed the labels for variants which are often colloquially named after the places where they are first detected.
Many variants of Sars-CoV-2 – the virus that causes Covid-19 – have been identified around the world.
They include B.1.1.7, known in the UK as the Kent variant and around the world as the UK variant – but now labelled by the WHO as Alpha.
The B.1.617.2 variant, often known as the Indian variant, has been labelled Delta, while B.1.351, often referred to as the South African variant, has been named Beta.
The P.1 Brazilian variant has been labelled Gamma.
The WHO said these labels were chosen after wide consultation and a review of many naming systems.
The organisation said the labels do not replace existing scientific names, which convey important scientific information and will continue to be used in research.
“While they have their advantages, these scientific names can be difficult to say and recall, and are prone to misreporting,” the WHO said.
“As a result, people often resort to calling variants by the places where they are detected, which is stigmatising and discriminatory.
“To avoid this and to simplify public communications, WHO encourages national authorities, media outlets and others to adopt these new labels.”
Meanwhile, the heads of the WHO, International Monetary Fund, World Bank Group and World Trade Organisation warned of a “dangerous gap” in the availability of covid jabs, with low-income nations receiving “less than 1% of vaccines administered so far”.