A medical conference held in late February in Boston may have caused up to 300,000 coronavirus infections, new study finds

• A late February medical conference in Boston, Massachusetts may have led to 300,000 cases of the novel coronavirus, a new report found.
• The Biogen medical conference took place on February 26, and 27, and had been directly linked to 100 cases through contact tracing,
• 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.

A Biogen medical conference in late February led to between 205,000 to 300,000 COVID-19 infections from February to November of this year, according to a study in the peer-reviewed journal Science by the American Association for the Advancement of Science.

The number does not account for transmissions of the virus after November 1.

According to the report, published Thursday, contact tracers had initially traced about 100 cases to the conference at the outset of the pandemic in the US, sparking concerns that it had been a super spreader event. According to the report, scientists studied the genetic code of COVID-19, which like all viruses, mutates as it spread, as CBS News noted.

Tracking the genetic code of the virus allowed the researchers draw their conclusions about how the virus spread following the February conference.

"We don't think these strains had a propensity to spread more than any other," Jacob Lemieux, the lead author of the study, told CBS News. "We suspect that these types of events have been happening over and over again, and are major contributors to the propagation and spread of SARS-cov2 throughout the world.

"The conditions that allow these super-spreading events to occur are very much still with us and will continue to be with us for a long time," he added.

In the four counties that comprise the Boston region, 51,000 - about half - of the cases of COVID-19 until the beginning of November had genetic markers that linked the cases to the conference, according to the report. The virus also spread from the conference to other states at the beginning of March, when the conference attendees returned to their home states, according to the article.

In total, COVID-19 cases linked to the Biogen conference were found in 29 states, according to the report, with 29% of the cases with the genetic marker from the conference found in the state of Florida, the report found. The scientists also found cases in Indiana and North Carolina.

Lemieux told CBS the conference attendees "tended to be younger, healthier, and were traveling more, and we found that they went to a lot of different places," leading to the high level of spread from the conference compared to other superspreader events that had far smaller implications.

Cases of the virus linked to the Boston conference were also found beyond the US, including in Australia, Sweden, and Slovakia, the scientists found.