There was a lot of speculation about that, but nothing proven, there was about three dozen cases linked to the festival, but it was attended by around 250,000 people over three days, so the number of cases were tiny, and they could have picked it up elsewhere, in particular on public transport going to or from the event.
And, people are packed in far tighter there, and at football matches, compared to Soho last night, and what we have seen during the protests & crowded beaches, and no spikes have been linked to those events.