Omicron Hospital Risk Is Up to 70% Lower Than Delta, U.K. Says

(Bloomberg) -- Omicron appears to be less severe but more contagious than any other Covid-19 strain to date, the U.K. government said, as daily infections soared to another new record close to 120,000. 

An individual with omicron is 50% to 70% less likely to be admitted to hospital, compared with the delta strain, the U.K. Health Security Agency said Thursday. They are also between 31% and 45% less likely to attend emergency departments with omicron than with delta.

However, data from the HSA also showed that while a booster improves protection, it starts to wane more rapidly than with delta, and is 15% to 25% lower from 10 weeks after the third dose. 

The agency also cautioned that the highly infectious nature of the variant could still lead to significant numbers of severe illness that squeeze the health service. Daily cases in the U.K. soared to a new record on Thursday, piling pressure on Prime Minister Boris Johnson, who is waiting until after Christmas to make a final decision on new possible restrictions. 

Johnson’s being squeezed between warnings from his scientific advisers about dangers to the health system and pressure from a large group within his own party who are against new curbs.

The HSA said 14 people have died within 28 days of an omicron diagnosis, ranging in age from 52 to 96.  

“Cases of the variant continue to rise at an extraordinary rate,” Health Secretary Sajid Javid said. “Hospital admissions are increasing, and we cannot risk the NHS being overwhelmed.”

Booster Effect 

It’s still unclear how the decreasing booster effect will factor into protection against severe disease. The current round of booster shots may still protect people from being hospitalized or getting severely ill, even as defense against infection wanes. U.K. officials want to see how that data develops before recommending a fourth dose, or moving toward a vaccine modified for omicron.

The HSA assessment on severity backs up studies published Wednesday that drew similar conclusions.

The agency said the data is still preliminary and further study is needed. Britain has embarked on an accelerated booster program in a bid to try and neutralize the impact of the fast-spreading omicron. 

Israel has already announced it will give people over 60 a fourth dose over fears that a booster that has not been administered within the last three to four months has lower protection against omicron. 

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