Who is mu?

A new coronavirus variant named Mu has been designated a variant of interest by the World Health Organization. Mu, or B.1.621, was first identified in Colombia and cases have been recorded in South America and Europe. Mu is the fifth variant of interest to be monitored by the WHO since March. There are also four “variants of concern” the health agency tracks—alpha, beta, gamma and delta—which, in addition to meeting the criteria to be a variant of interest, have more significant changes, such as reducing the effectiveness of vaccines. While wealthy countries hoard limited vaccine supplies for booster campaigns, many parts of the world have not yet had a chance to begin vaccinating. Limited vaccine coverage and the rapid spread of the coronavirus makes an ideal environment for new virus variants to emerge. The WHO said it would be monitoring “the epidemiology of the mu variant in South America, particularly with the co-circulation of the delta variant… for changes”