In late February, Biogen held a medical conference in Boston, Massachusetts.
According to Business Insider, contact tracing revealed 100 cases of COVID-19 were directly linked to the event.
And a new report finds that those cases, in turn, may have led to 300,000 new cases of the novel coronavirus.
By studying and tracing the genetic code of the virus, scientists determined up to 300,000 cases could be attributed to the conferences through November 1.
COVID-19 cases linked to the Biogen conference were found in 29 states.
29% of the cases with the genetic marker from the conference were found in the state of Florida. Cases were also found in Indiana and North Carolina.