Health officials are watching another new coronavirus variant, dubbed "mu," which they say has concerning mutations that could allow it to escape vaccine-induced immunity.
The variant, also known as B.1.621, was first detected in Colombia in January 2021, according to the World Health Organization (WHO). On Monday (Aug. 30), WHO classified it as a "variant of interest," or VOI, and named it mu.
The VOI label means the variant is increasing in prevalence in multiple areas and has mutations that are likely to affect viral characteristics, such as transmissibility or disease severity, Live Science previously reported. In contrast, officials use the term "variant of concern," or VOC, once reliable data show that the variant has increased transmissibility — such as what's been seen with the delta variant — or other worrisome features, such as the ability to evade vaccines.