South Africa Has Likely Passed the Peak of Omicron COVID Cases, Indicating a Shorter Wave for U.S.

South Africa COVID
South Africa COVID

MICHELE SPATARI/AFP via Getty COVID-19 testing in South Africa

South Africa appears to have passed the peak of COVID-19 infections from the omicron wave, researchers said. It could be an indication that the variant moves quickly before dying down, providing a timeline for the U.S. as cases ramp up.

After detecting their first case of the omicron variant in late November, South Africa has "surpassed the peak of the Omicron wave now, driven by the significant decline in the populous province and epicenter: Gauteng," Ridhwaan Suliman, senior researcher at the South African Council for Scientific and Industrial Research, told CNN on Wednesday.

The country saw their highest case total of 27,000 new infections on Thursday, and numbers have since dropped down to 15,424 on Tuesday. And in the Gauteng province, South Africa's largest with 16 million people and the city of Johannesburg, cases dropped even earlier, a trend that has continued in the week since.

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A second researcher, from the Vaccines and Infectious Diseases Analytics department of the University of Witwatersrand, noted the same trend to the Associated Press.

"The drop in new cases nationally combined with the sustained drop in new cases seen here in Gauteng province, which for weeks has been the center of this wave, indicates that we are past the peak," said senior researcher Marta Nunes.

South Africa's experience with omicron could predict the next few weeks of spread in the U.S., where cases with the variant are now dominating. If South Africa's trend holds, the U.S. could see a peak in cases in January before dying down.

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The U.S. Centers for Disease Control said Monday that between Dec. 12 and 18, omicron made up 73% of all new COVID-19 cases in the country, a major jump from the week prior when it accounted for just 12%.

RELATED: COVID Variant Omicron Now Accounts for More Than 70 Percent of U.S. Cases, CDC Says

Omicron appears to cause more breakthrough infections in people who are vaccinated against COVID-19 than previous variants like delta. A large, real-world study of COVID-19 patients in South Africa found that Pfizer's two-dose vaccine is just 30% effective at preventing infection with omicron, a significant drop from the 80% protection it had against earlier variants.

However, Pfizer's vaccine was still highly effective in preventing severe illness from omicron. The two-dose series still protected people from needing hospitalization 70% of the time; "very good protection," the study authors said. And in a study from the U.K., a booster dose significantly increased protection, pushing the effectiveness at preventing infection to 75%.

Last month, the CDC expanded its vaccine booster recommendations for Americans following the arrival of omicron in North America.

The spread of the variant "further emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19," the CDC said. "Early data from South Africa suggest increased transmissibility of the Omicron variant, and scientists in the United States and around the world are urgently examining vaccine effectiveness related to this variant."

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