Dataset Information

Transmission from vaccinated individuals in a large SARS-CoV-2 Delta variant outbreak.

ABSTRACT: An outbreak of over 1,000 COVID-19 cases in Provincetown, Massachusetts (MA), in July 2021-the first large outbreak mostly in vaccinated individuals in the US-prompted a comprehensive public health response, motivating changes to national masking recommendations and raising questions about infection and transmission among vaccinated individuals. To address these questions, we combined viral genomic and epidemiological data from 467 individuals, including 40% of outbreak-associated cases. The Delta variant accounted for 99% of cases in this dataset; it was introduced from at least 40 sources, but 83% of cases derived from a single source, likely through transmission across multiple settings over a short time rather than a single event. Genomic and epidemiological data supported multiple transmissions of Delta from and between fully vaccinated individuals. However, despite its magnitude, the outbreak had limited onward impact in MA and the US overall, likely due to high vaccination rates and a robust public health response.

SUBMITTER: Siddle KJ

PROVIDER: S-EPMC8695126 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Transmission from vaccinated individuals in a large SARS-CoV-2 Delta variant outbreak.

Siddle Katherine J KJ Krasilnikova Lydia A LA Moreno Gage K GK Schaffner Stephen F SF Vostok Johanna J Fitzgerald Nicholas A NA Lemieux Jacob E JE Barkas Nikolaos N Loreth Christine C Specht Ivan I Tomkins-Tinch Christopher H CH Paull Jillian S JS Schaeffer Beau B Taylor Bradford P BP Loftness Bryn B Johnson Hillary H Schubert Petra L PL Shephard Hanna M HM Doucette Matthew M Fink Timelia T Lang Andrew S AS Baez Stephanie S Beauchamp John J Hennigan Scott S Buzby Erika E Ash Stephanie S Brown Jessica J Clancy Selina S Cofsky Seana S Gagne Luc L Hall Joshua J Harrington Rachel R Gionet Gabrielle L GL DeRuff Katherine C KC Vodzak Megan E ME Adams Gordon C GC Dobbins Sabrina T ST Slack Sarah D SD Reilly Steven K SK Anderson Lisa M LM Cipicchio Michelle C MC DeFelice Matthew T MT Grimsby Jonna L JL Anderson Scott E SE Blumenstiel Brendan S BS Meldrim James C JC Rooke Heather M HM Vicente Gina G Smith Natasha L NL Messer Katelyn S KS Reagan Faye L FL Mandese Zoe M ZM Lee Matthew D MD Ray Marianne C MC Fisher Marissa E ME Ulcena Maesha A MA Nolet Corey M CM English Sean E SE Larkin Katie L KL Vernest Kyle K Chaluvadi Sushma S Arvidson Deirdre D Melchiono Maurice M Covell Theresa T Harik Vaira V Brock-Fisher Taylor T Dunn Molly M Kearns Amanda A Hanage William P WP Bernard Clare C Philippakis Anthony A Lennon Niall J NJ Gabriel Stacey B SB Gallagher Glen R GR Smole Sandra S Madoff Lawrence C LC Brown Catherine M CM Park Daniel J DJ MacInnis Bronwyn L BL Sabeti Pardis C PC

Cell 20211223 3

An outbreak of over 1,000 COVID-19 cases in Provincetown, Massachusetts (MA), in July 2021-the first large outbreak mostly in vaccinated individuals in the US-prompted a comprehensive public health response, motivating changes to national masking recommendations and raising questions about infection and transmission among vaccinated individuals. To address these questions, we combined viral genomic and epidemiological data from 467 individuals, including 40% of outbreak-associated cases. The Del ...[more]

PMID: 35051367

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Dataset Information

Transmission from vaccinated individuals in a large SARS-CoV-2 Delta variant outbreak.

Publications

Transmission from vaccinated individuals in a large SARS-CoV-2 Delta variant outbreak.

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