By CBSBoston.com Staff

BOSTON (CBS) – Friday marks the first anniversary of what is believed to be the first coronavirus super spreader event in Massachusetts, the Biogen conference in Boston.

Ninety-nine of the 175 people who attended the two-day conference at the Marriott Long Wharf on February 26 and 27, 2020 tested positive for COVID-19. Those people then carried the virus across Massachusetts and different parts of the country and the world at a time when little was known about it and the importance of masks and social distancing.

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A study released in December suggested the conference could be connected to up 300,000 coronavirus cases as of November 1. Cases were traced as far away as Australia, Slovakia, and Sweden. The study estimated the conference is responsible for about 1.6% of all coronavirus cases in the United States.

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“In this particular event is was sort of like a perfect storm for a respiratory virus like this to spread that quickly,” Tufts Medical Center Infectious Disease physician Dr. Gabriela Andujar Vasquez told WBZ-TV last August.

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Biogen is based in Cambridge. It develops therapies for neurological diseases.

CBSBoston.com Staff