Omicron probably the biggest threat of Covid pandemic, says health chief

Head of UK Health Security Agency warns MPs to expect staggering' growth rate in coming days

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The head of the UK Health Security Agency has called the Omicron variant probably the most significant threat" since the start of the pandemic as she told MPs to expect a staggering" growth rate over the coming days.

Dr Jenny Harries told the Commons transport select committee on Wednesday that it was still too early to judge the potential risk of the new Covid variant and warned that the virus was growing faster".