Real-world data shows boosters work against Omicron, offering 'remarkable' protection against hospitalization for at least 3 months
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- Boosters offer "remarkable" protection against hospitalization with Omicron.
- Real-world data suggests they're 89% effective against hospitalization for at least three months.
- Hospitalization rates for unvaccinated Americans over 55 were 44 times higher than for boosted people.
Boosters offer strong protection against Omicron hospitalizations, real-world data from the US and UK suggests.
The data comes as only about half of fully vaccinated Americans have had a booster and 20% of Americans remain unvaccinated, official data shows.
Unvaccinated Americans aged 55 and older were at least 44 times more likely to be admitted to hospital with COVID-19 than those who'd had booster shots in December, according to Centers for Disease Control and Prevention data released Thursday. The data comes from 250 hospitals across 14 states.
Another preliminary study from researchers at Kaiser Permanente Southern California found three doses of Pfizer's shot was about 89% effective against hospitalization and held for at least three months.
Protection against Omicron hospitalization from two doses was 68% from six weeks after the second dose, the study authors said Tuesday. The findings were based on 8,694 hospital admissions to Kaiser Permanente between December 1, 2021, and January 11.
The study authors said that two doses of Pfizer vaccine was no longer sufficient and booster doses were needed. "Achieving high levels of booster coverage is an urgent global public health priority", they said.
The study is Pfizer-funded and hasn't yet been published or formally scrutinized by other experts but its findings reflect UK data.
The UK Health and Security Agency said in a report Thursday that from two weeks after a booster, that from two weeks after a booster, protection from existing vaccines against hospitalization with Omicron was about 89%, waning slightly to 83% at 10 weeks. For comparison, from two to 25 weeks after the second dose, protection against Omicron hospitalization was 64%, the UKHSA said.
Data from Israel released Tuesday found there was no difference between people who got fourth doses, compared with those who got three.
Eric Topol, director of the Scripps Research Translational Institute, who wasn't involved in the studies, said of the Kaiser Permanente findings on Twitter Thursday: "Remarkable 90% and durable protection (>3 months) with booster vs Omicron vs hospital admission, the 1st US data, confirms + extends @UKHSA data."
The data from the US and UK highlight the power of vaccines, especially boosters, at stopping people getting really sick when health systems are stretched and Omicron cases for all ages have soared. Doctors in the US have urged people to get vaccinated and boosted.
It also suggests that most people won't need extra fourth doses for Omicron — existing vaccines are still working against severe illness caused by the variant.
Longer-term durability of protection beyond three months from booster doses isn't yet known.