Covid live: fourth vaccine dose ‘could be needed against Omicron’; not enough data on severity, says WHO

Latest updates: German health minister says offensive booster campaign' needed to fight variant; WHO official says it is too early to draw conclusions on severity

• WHO's Europe chief says another storm coming' as Omicron takes hold
• AstraZeneca aims to produce Omicron-targeted vaccine with Oxford
• Boris Johnson confirms no new Covid restrictions in UK before Christmas
• Risk of hospital stay 40% lower with Omicron than Delta - UK data
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Researchers in Melbourne, Australia, have turned one of the world's most-used blood-thinning drugs into a nasal spray which they hope could prevent Covid-19 transmission.

Northern Health medical divisional director Don Campbell and researchers at Melbourne, Monash and Oxford Universities found that heparin can block the transmission of Covid-19 and prevent infection.

It won't matter if a new variant comes along, this drug will block that protein from infecting the cells.

I'm very confident that we can demonstrate that it will work, and people will be using this before they go to the shops and before they go to school."

Due to large-scale flooding near the Port of Vancouver ... and the global supply chain crunch caused by the coronavirus pandemic, there are delays in the supply of potatoes."