What’s known and unknown about Omicron, the coronavirus variant identified in South Africa

Scientists in South Africa have identified a new coronavirus variant with a worrisome combination of mutations that experts fear could make it more transmissible and allow it to evade immune protection — including the protection generated by vaccines.

Experts are scrambling to learn more about the variant, known by its scientific name B.1.1.529 and called Omicron by the World Health Organization. Right now, there are more open questions than firm answers. And although scientists have expressed significant early concern over the variant — the WHO designated it as a “variant of concern” on Friday — they have cautioned that they are still seeking critical information about it.