COVID cases surge in South Africa in sign Omicron wave is coming

South Africa alerted the world to the Omicron variant. Now data out of South Africa may serve as a warning of what we're facing.

Driving the news: South Africa recorded 11,535 new cases Thursday with 22.4% of tests coming back positive — up from an average of about 300 new cases, with a 2% test positivity rate 10 days earlier. The country's top public health officials expect that exponential rise to continue as Omicron rapidly becomes the dominant variant.

• Meanwhile, preliminary evidence from South Africa's National Institute for Communicable Diseases (NICD) suggests people who were previously infected with COVID-19 are three times more susceptible to reinfection from Omicron than from prior strains.
• "We believe that previous infection does not provide protection from Omicron," said Anne von Gottberg, who heads NICD’s respiratory diseases laboratory. "We believe the number of cases will increase exponentially in all provinces of the country. We believe that vaccines will still, however, protect against severe disease."
• The NICD study did not examine the effectiveness of vaccines at preventing infection. Experts worry Omicron’s high number of mutations may render vaccines significantly less effective.

What's next: We’ll soon have a sense of how infectious Omicron is compared to previous strains, experts say, but it will take longer to determine whether it causes more serious disease.

Zoom in: Stores and restaurants in Johannesburg remain crowded, the BBC’s Pumza Fihlani reports, and President Cyril Ramaphosa is resisting the idea of fresh lockdowns, instead stressing the need to accelerate vaccination.

• 24% of South Africans and 41% of adults are currently vaccinated in the country — among the highest rates in Africa but far behind many wealthy countries. Supply had long been the major roadblock, but Ramaphosa is now focused on reducing vaccine hesitancy.
• In a televised address on Sunday, he announced "consultations" on potentially “making vaccination mandatory for specific activities and locations.”
• The rate of vaccinations in South Africa had been falling for several weeks but has begun to tick upward since news of the new variant emerged.

Zoom out: The Omicron threat has convinced countries to push ahead with policies to encourage or mandate vaccination.

• The German government Thursday announced a "lockdown of the unvaccinated" — banning them from all businesses except essential ones like grocery stores and pharmacies — and said a nationwide vaccine mandate could become effective in February 2022.
• Greece plans to make residents over 60 get a shot or pay a monthly fine.

The big picture: Many rich-world leaders, President Biden among them, are ruling out new lockdowns but pushing booster shots, rapid tests and masks.

Omicron's clearest effect to date is on travel, with bans continuing to be announced (mostly on southern Africa) and would-be tourists around the world reconsidering their plans.

• Even beyond COVID-19, border controls will increasingly become a weapon against infectious disease — whether or not public health experts agree they are effective, Axios' Bryan Walsh writes.

Worth noting: It emerged on Tuesday that an Omicron case was detected in the Netherlands on Nov. 19, days before the variant's detection was announced by South African scientists.

Go deeper: Omicron upends holiday travel plans