Illustration: Brendan Lynch/Axios
New data from South Africa and Europe hint that Omicron cases are poised to explode in the U.S., where the vast majority of the population isn't well protected against infection.
Driving the news: A new analysis by South Africa's largest private insurer paints a picture of Omicron's clinical risk: Two doses of Pfizer's vaccine appear to be significantly less effective against severe disease with Omicron than previous variants.
- But the variant is less likely to lead to hospitalization in adults than the original version.
What they're saying: "Everything points to a large wave. A large wave is coming," a senior Biden administration official told Axios.
- "It will be fast. It won't be as severe, but regrettably, there will be plenty of hospitalizations," the official added.
By the numbers: The South African analysis, by Discovery Health, found that the risk of hospital admission among adults diagnosed with the Omicron variant is 29% lower than it was during South Africa's first wave of infections in 2020. The researchers adjusted their calculations by vaccination status.
- Their vaccine effectiveness analysis included more than 211,000 positive COVID-19 test results, from which 41% were from adults who'd received two doses of the Pfizer-BioNTech vaccine.
- During the current Omicron wave, the two-dose regimen was 70% effective against severe disease requiring hospital admission. (Vaccine effectiveness is measured against the same risk in the unvaccinated.)
Yes, but: It also found that two doses of the Pfizer vaccine are only 33% effective against infection from Omicron.
The big picture: A dramatic surge in cases could still overwhelm our burnt-out health system if even a small percentage require hospital care.
- The analysis found that vaccinated elderly people have slightly less protection against hospitalization, reinforcing the importance of booster shots in this age group.
- They found children had a 20% higher risk of hospital admission than they did from previous variants.
State of play: The Delta variant is already driving yet another surge of cases and hospitalizations in the U.S. Omicron seems poised to make this significantly worse, given its high transmissibility and its ability to evade immune protection.
- In Denmark, where about 80% of the population has been vaccinated, three-fourths of Omicron cases are among fully vaccinated people, and another 9% are among those who have received a booster shot, according to a report released by the Statens Serum Institut yesterday.
- European countries have also been reporting that the variant is spreading rapidly, with cases doubling every two to three days.
- Omicron's "exponential rise could take us to levels of even 1 million cases per day in the United States, which previously would have been considered an unthinkable projection," Scripps Research's Eric Topol wrote yesterday on Substack.
Yes, but: We don't have nearly enough data yet to make any firm predictions.
- In South Africa, for example, case growth also appears to be slowing down, and there have been reports that hospitalized adults are less sick than in previous waves.
- "The chances that those vaccines will continue to provide protection against serious illness against Omicron are very good," said Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia.
The bottom line: "Frankly we don't have enough reliable, robust data at this point to give a clear direction as to what this will look like in the weeks to months ahead," said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.
- But there is certainly a strong possibility that a lot of Americans are about to get sick — soon.