The United Kingdom is taking quick action to stop the spread of the omicron variant of the COVID-19 virus.
Prime Minister Boris Johnson announced a push to make a booster available to everyone 18 and older by the end of the year, one month ahead of the earlier target.
About 10 people are in U.K. hospitals with omicron, and Johnson on Monday reported the country's first COVID-19 omicron death.
Johnson said boosters would "reinforce our wall of vaccine protection" against an anticipated "tidal wave of omicron."
"The idea that this is somehow a milder version of the virus, I think that's something we need to set on one side and just recognize the sheer pace at which it accelerates through the population," Johnson said as he visited a vaccination center in London. "So the best thing we can do is all get our boosters."
The British government raised the country's coronavirus threat level on Sunday, warning that the rapid spread of omicron "adds additional and rapidly increasing risk to the public and health care services."
Long lines formed at vaccination centers across Britain early Monday morning.
U.K. health authorities say omicron cases are doubling every two to three days in Britain, and it will replace delta as the dominant COVID-19 strain within days.
More than 80% of people age 12 and up in Britain have received two vaccine doses, and 40% of adults have had three. Giving the rest of adults boosters by the end of the month will be a huge challenge, requiring almost 1 million vaccine shots a day. Johnson acknowledged that many routine medical procedures would have to be postponed to meet the goal.
Scientists in South Africa, where omicron was first identified, say the variant may cause less severe disease than delta but caution that it's too soon to be certain.
Health authorities around the world are watching Britain closely to see what an omicron surge looks like in a country with an older, more highly vaccinated population than South Africa's.
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