Covid news: Boris Johnson unveils booster plan; South African president tests positive – as it happened

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Dr Susan Hopkins, chief medical adviser for the UK Health Security Agency, has warned that very difficult" decisions lie ahead for the government and that more Covid measures may be needed.

She told the BBC's The Andrew Marr Show:

I think that the restrictions that the government have announced are sensible. I think that we may need to go beyond them. But we'll need to watch carefully what happens with hospitalisations.

The challenge we have and the challenge government has is trying to balance the risks and benefits to the society, to people, to the population, to the economy, and to health, and they have very difficult decisions ahead of them.