scientists in Colombia discovered a worrisome new coronavirus variant

Mu spread swiftly in Colombia, fueling a new surge of Covid-19 cases

For every Delta or Omicron there is a Gamma, Iota or Mu, variants that drove local surges but never swept to global dominance

 while understanding Omicron remains a critical public health priority, there are lessons to be learned from these lesser lineages

Studies of the also-rans have shed light on surveillance gaps and policy blunders 

The research also highlights how much context matters; variants that make an impact in some places never gain a foothold in others

predicting which variants will surge to dominance is difficult, and staying on top of future variants

For more stories