Where did the spread initiate? Essentially, was this a superspreading event during which someone — likely an unvaccinated person — passed the virus to the eight people? That is one probable explanation. The SARS-CoV-2 coronavirus is particularly adept at transmitting in crowded, indoor settings, so perhaps someone who was shedding lots of virus came into contact with the team, and that’s how this outbreak occurred. The Yankees have surpassed the threshold of 85% players and personnel vaccinated that allowed them under league and union rules to relax some distancing and masking requirements. It’s also possible that some of the transmission occurred among the eight people who’ve tested positive, though that would seem to be a rarer event. Even if a vaccinated person contracts the coronavirus, it seems they’re generally less infectious to others than an unvaccinated person with Covid-19 — especially if they’re asymptomatic. That might be because the vaccine reduces the amount of virus these people can shed, and also shrinks the window during which they’re contagious.