COVID cases are breaking records in an all-time surge in 4 countries known to have the biggest Omicron outbreaks

• Omicron is spreading more quickly than previous variants, new data increasingly shows.
• The UK, Norway, Denmark, and South Africa detected Omicron outbreaks and now record daily cases.

Coronavirus infections in four countries skyrocketed to record-breaking rates after the Omicron variant was found to be spreading there.

Experts fear that the sharp trajectory in South Africa, the UK, Norway, and Denmark could be replicated more widely as other countries see Omicron cases pick up in their populations.

In all four countries named above, the rates of infection are the highest at any time since the pandemic began.

"It really is exponential growth the likes of which we haven't seen since the pandemic started." Eric Topol, director at Scripps Research Institute, said in an interview with PBS News Hour on Thursday.

He said that it was "unquestionable" that the US is also heading to a "bad winter."

Below are the first and second highest rates in these four countries expressed as seven day average of daily new COVID-19 cases per million:

• Denmark — 1,320 recorded on December 16, 2021; 606 on December 20, 2020.
• UK — 920 on December 16, 2021; 876 on Jan 10, 2020.
• Norway — 876 on December 16, 2021; 267 on Sept 5, 2021.
• South Africa — 386 on December 16, 2021; 332 on July 6, 2021.

The increase comes after all four countries have reported a rapid spread of Omicron, which has been spotted by South Africa as early as November 9, per the World Health Organization.

All four countries have raised alarms about the spread of Omicron.

South Africa reported that Omicron made up 78% of sequenced cases in November.

Norway and Denmark expect the variant to overtake Delta in a matter of days, while Omicron already makes up more than a third of the cases in most UK regions.

Norway, Denmark, and the UK have all had comprehensive vaccine rollouts, which seemingly did little to prevent the spread of the variant.

"It's inevitable" that the US will start seeing an increase in cases, Topol said. "It already is rising very quickly," he said.

Omicron made up about 3% of US cases, per CDC data from December 11.

Omicron is doubling in just over two days, Topol said. "We've never seen anything like that," he said.

Hospitalization and deaths, in the four spiking countries, however, have remained relatively low.

That is a sign that vaccination could be aiding in controlling the worst of this outbreak, Topol said.

Experts have warned, however, that a very heavy caseload could still lead to hospitals being overwhelmed even if only a small proportion of cases are serious.

Resistance to severe illness is likely due to immunity built by vaccination rates and previous exposure in these countries, Topol said.

"There isn't any question, fortunately, that it's milder," Topol said, adding: "The problem is that people are ascribing that to the virus. And it's not related to the virus, it's because we have so much immunity"

"We have to assume that people who don't have any protection are highly vulnerable to getting very ill," Topol said.