The WHO is announcing a new nomenclature for the COVID-19 variants that were previously — and somewhat uncomfortably — known either by their technical letter-number codes or by the countries in which they first appeared. Hoping to strike a fair and more comprehensible balance, WHO said it will now refer to the most worrisome variants — known as “variants of concern” — by letters in the Greek alphabet. So the first such variant of concern, which first appeared in Britain and can be also known as B.1.1.7, will be known as the “alpha” variant.