Covid vaccine: what does the Pfizer vaccine news mean?

There has been some promising Covid-19 vaccine news.

A preliminary analysis shows the first effective coronavirus vaccine can prevent more than 90% of people from getting Covid-19.

But there's still a way to go before any vaccine can be given to the wider public and our lives can go back to how they were pre-pandemic.

BBC health correspondent Laura Foster helps puts this news into context.

Video by Laura Foster and Terry Saunders