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The new omicron variant could increase the likelihood that people will need a fourth coronavirus vaccine dose earlier than expected, executives at pharmaceutical giant Pfizer said Wednesday. Boosters are likely to help control the variant, according to the company, which said early lab experiments suggest that the standard two-dose regimen still provides some protection against severe illness from the variant.

Albert Bourla, Pfizer’s chief executive, had projected that a fourth dose might be needed 12 months after a third shot. But he said on CNBC’s “Squawk Box” that the timeline might need to be moved up. One of the company’s top scientists recently said a fourth shot — possibly one targeting omicron — is likely to be necessary.

More than 40 people in the United States have tested positive for the omicron variant, the director of the Centers for Disease Control and Prevention told the Associated Press on Wednesday. Nearly all of them showed mild symptoms, she said. Elsewhere, the World Health Organization said Wednesday that omicron cases have been reported in 57 countries so far.

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