Shiraaz Mohamed, The Associated Press

A woman is vaccinated against COVID-19 at the Hillbrow Clinic in Johannesburg, South Africa, Monday Dec. 6, 2021. South African doctors say the rapid increase in COVID-19 cases attributed to the new omicron variant is resulting in mostly mild symptoms.

By Laura Ungar and Andrew Meldrum | The Associated Press

PUBLISHED: December 6, 2021 at 9:30 p.m. | UPDATED: December 6, 2021 at 9:46 p.m.

Omicron v. delta: Battle of coronavirus mutants is critical

Many critical questions about omicron remain unanswered, including whether the virus causes milder or more severe illness