On the nightly news here in the US they report "up to" 90% when the story first broke. I am 100% certain of that.
and of course all news media outlets and generalists always give completely accurate information and reports literally to the very last word and we should trust their every word of their news reports as completely reliable and accurate with absolutely no possibility they may have got just one small piece of information a bit inaccurate if not wrong. 😕
Its a fair bet that the direct scientific report, not the generalists or news outlet reports, doesn't mention "up to" 90%.
"...Coronavirus vaccine candidate being developed by Pfizer is ‘more than
90% effective’ ..." (my emphasis)
How can it be both "up to" 90% and "more than" 90% ?
Obviously at least one of those two news reports must have got that part a bit wrong.
Most of the news outlets I have seen just say "90% effective" just as if that's not "up to" 90% in particular nor "more than" 90% in particular but rather just approximately 90%.
"...Pfizer’s Covid-19 vaccine candidate, of which the UK Government has secured 10m doses for use ‘by the end of the year’, is ‘90%’ effective, the company has announced today...."
which is why in my OP I said "...about 90% effective..."