It it not clear how many of the 12,000 attendees at the first major conference since the pandemic were infected.Biden meets Johnson, announces U.S. will donate Covid vaccine dosesJune 10, 202101:42June 11, 2021, 12:20 AM UTCBy MacKenzie Sigalos

Some of the 12,000 attendees who flew into Miami last weekend for the biggest bitcoin event in history have since tested positive for Covid-19.

It is not clear how many attendees were infected.

Bitcoin 2021 drew crypto enthusiasts from around the world to the Mana Wynwood convention center in Miami’s arts and entertainment district. Attendees packed into auditoriums and networked for the three-day event. It was the first major conference since the pandemic started, and many attendees said they were relieved to be out among colleagues trading news and updates.

There was no mask mandate and no proof of vaccination requirement to attend. Covid was only a talking point in the context of how thrilled everyone was to have arrived at the other side of the pandemic.

That is, of course, until some conference participants took to Twitter to say they had tested positive for the coronavirus.

The #Bitcoin 2021 conference in Miami was the first major in-person conference since the pandemic started.

It may have been a “super spreading event” as dozens of participants reveal they’ve tested positive for COVID-19. pic.twitter.com/jdYnl6PgsR

— Mr. Whale (@CryptoWhale) June 10, 2021

In the spirit of full disclosure, I attended the show after receiving two doses of the Moderna vaccine this spring. A vaccination isn’t a 100 percent guarantee of immunity, but at the moment, I’m not presenting any symptoms. Many of my conversations with Uber and Lyft drivers started with a mutual discussion of having been vaccinated.

Whether the conference is ultimately billed as a super spreader event remains to be seen.

Everyone who I hung out with in Miami got covid. Luckily for me I hung out about one feet above everyone

— Larry Cermak (@lawmaster) June 10, 2021

It is unclear whether the city of Miami had a contingency plan in place for this kind of outcome. The mayor’s office and conference organizers did not immediately respond to CNBC’s request for comment.

On Tuesday, Florida said it will no longer report daily Covid cases and fatalities as vaccinations rise and it begins shifting to the “next phase” of the pandemic. Florida reported an average of eight new cases per 100,000 residents over the past week, according to data compiled by Johns Hopkins University, far below its pandemic high of 84 per 100,000.