@article {664375,
	title = {Phylogenetic analysis of SARS-CoV-2 in the Boston area highlights the role of recurrent importation and superspreading events },
	year = {2020},
	abstract = {
	SARS-CoV-2 has caused a severe, ongoing outbreak of COVID-19 in Massachusetts with 111,070 confirmed cases and 8,433 deaths as of August 1, 2020. To investigate the introduction, spread, and epidemiology of COVID-19 in the Boston area, we sequenced and analyzed 772 complete SARS-CoV-2 genomes from the region, including nearly all confirmed cases within the first week of the epidemic and hundreds of cases from major outbreaks at a conference, a nursing facility, and among homeless shelter guests and staff. The data reveal over 80 introductions into the Boston area, predominantly from elsewhere in the United States and Europe. We studied two superspreading events covered by the data, events that led to very different outcomes because of the timing and populations involved. One produced rapid spread in a vulnerable population but little onward transmission, while the other was a major contributor to sustained community transmission, including outbreaks in homeless populations, and was exported to several other domestic and international sites. The same two events differed significantly in the number of new mutations seen, raising the possibility that SARS-CoV-2 superspreading might encompass disparate transmission dynamics. Our results highlight the failure of measures to prevent importation into MA early in the outbreak, underscore the role of superspreading in amplifying an outbreak in a major urban area, and lay a foundation for contact tracing informed by genetic data.

},
	url = {https://www.medrxiv.org/content/10.1101/2020.08.23.20178236v1.article-info},
	author = {Lemieux J and Siddle KJ and Shaw BM and Loreth C and Schaffner S and Gladden-Young A and Adams G and Fink T and Tomkins-Tinch CH and Krasilnikova LA and Deruff KC and Rudy M and Bauer MR and Lagerborg KA and Normandin E and Chapman SB and Reilly SK and Anahtar MN and Lin AE and Carter A and Myhrvold C and Kemball M and Chaluvadi SR and Cusick C and Flowers K and Neumann A and Cerrato F and MR, Farhat and Slater D and Harris JB and Branda J and Hooper D and Gaeta JM and Bagett TP and O{\textquoteright}Connel J and Gnirke A and Lieberman TB and Philippakis A and Burns M and Brown C and Luban J and Ryan ET and Turbett SE and LaRocque RC and Hanage WP and Gallagher G and Madoff LC and Smole S and Pierce VM and Rosenburg ES and Sabeti S and Park DJ and MacInnis BL}
}
