Transmissability: Likely Increased.
Virulence: Likely Increased.
Antigenicity: Mu variant has mutations that have the potential to evade immunity provided by a previous COVID-19 infection or vaccination.
Spread: Outbreaks of the Mu variant were reported in South America and Europe. The lineage B.1.621 has a sublineage, labeled B.1.621.1 under the PANGO nomenclature, which has already been detected in more than 20 countries worldwide.
Global Positive Samples Sequenced: 5,628,545
B.1.621 Sequenced: 9,755
% of Global Samples Sequenced: 0.17%
Most common countries: United States of America 43.0%, Colombia 25.0%, Chile 9.0%, Spain 5.0%, Mexico 4.0% (Lineage predominantly in Colombia with several spike mutations, pango-designation issue #57)
Global Samples Sequencing Data
Updated December 2021