COVID-19’s Omicron variant continues to spread around the U.S. and the world, and the World Health Organization on Monday deemed it a “very high” global risk. But a study released Tuesday by Discovery Health, South Africa’s largest health insurer, offered more evidence that the new coronavirus strain causes milder illness, even as it evades some of the protections from the Pfizer-BioNTech vaccine. 

The study examined 211,000 positive COVID-19 cases, including 78,000 South Africans who contracted the Omicron variant. It found that hospital admissions are 29 percent lower among adults infected with the Omicron than in the first wave of the pandemic back in mid-2000, and those hospitalized had less serious symptoms. . 

Two doses of the Pfizer vaccine, the main vaccine in South Africa, provided just 33 percent protection against infection, much lower than against previous variants, but also provided 70 percent protection against severe symptoms that lead patients to be hospitalized, down from 90 percent against Delta, The Washington Post reports. That is still “very good protection,” the researchers said. Pfizer says a third booster dose raises protection back to Delta levels.