Volume 28, Number 1—January 2022
Multistate Outbreak of SARS-CoV-2 Infections, Including Vaccine Breakthrough Infections, Associated with Large Public Gatherings, United States
|Primary case, n = 26||Secondary case, n = 30|
|Sex||n = 26||n = 29|
|M||22 (85)||15 (52)|
|Age group, y||n = 26||n = 30|
|19–49||20 (77)||16 (53)|
|50–64||5 (19)||8 (27)|
|Race/ethnic group||n = 24||n = 25|
|Hispanic or Latino||1 (4)||3 (12)|
|Non-Hispanic White||16 (67)||13 (52)|
|Non-Hispanic Black||1 (4)||0|
|Non-Hispanic other race or multiracial
|Residence||n = 26||n = 30|
|Other area in Massachusetts||17 (65)||17 (57)|
|Not in Massachusetts
|Vaccination status‡||n = 26||n = 30|
|Previous COVID-19 illness§||n = 24||n = 29|
|Previous COVID-19 diagnosis||1 (4)||1 (3)|
|Duration since previous positive test result, d
|Underlying medical conditions¶||n = 26||n = 30|
|Symptoms||n = 25||n = 26|
|Asymptomatic||1 (4)||1 (4)|
|Symptoms reported||n = 24||n = 22|
|Abdominal pain||3 (13)||1 (5)|
|Chills||13 (54)||7 (32)|
|Congestion||14 (58)||13 (59)|
|Cough||16 (67)||14 (64)|
|Diarrhea||6 (25)||5 (23)|
|Difficulty breathing/shortness of breath||3 (13)||1 (5)|
|Fatigue||14 (58)||13 (59)|
|Fever||17 (71)||10 (45)|
|Headache||11 (46)||13 (59)|
|Loss of appetite||10 (42)||4 (18)|
|Loss of smell or taste||12 (50)||13 (59)|
|Muscle aches/pains||14 (58)||8 (36)|
|Sore throat||10 (42)||9 (41)|
|Time from symptom onset to specimen collection date, d||n = 23||n = 23|
|Range||0–9||−1 to 6|
|Clinical course||n = 26||n = 30|
|Admitted to hospital||1 (4)||0|
|Admitted to intensive care unit||0||0|
*Values are no. (%) unless indicated otherwise. Percentages might not total 100% because of rounding. Denominators for individual variables exclude cases that have missing data. COVID-19, coronavirus disease; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.
†A primary case was defined as detection of SARS-CoV-2 RNA or antigen in a respiratory specimen collected from a person <14 d after travel to or residence in Provincetown during July 3–17. A secondary case was defined as detection of SARS-CoV-2 RNA or antigen in a respiratory specimen collected from a person <14 d after close contact (within 6 feet for a cumulative total of >15 min within a 24-h period) with a person who had a primary case during their infectious period, and without history of travel to or residence in Provincetown during July 3–August 10. Secondary cases do not include chains of transmission occurring within visitors/residents in Provincetown. The infectious period of a person with a primary case was defined as 2 d previously through 10 d after symptom onset or, if asymptomatic, 2 d previously through 10 d after a positive test result. Only primary cases associated with a secondary case are presented.
‡Fully vaccinated persons were those who were >14 d after completion of all recommended doses of a US Food and Drug Administration‒authorized COVID-19 vaccine (2 doses of Pfizer/BioNTech [https://www.pfizer.com] or Moderna [https://www.modernatx.com], or 1 dose of Johnson & Johnson [https://www.jandj.com]), with documentation in their state immunization information system or self-report of vaccination details during case investigation.
§Previous COVID-19 illness was defined as detection of SARS-CoV-2 RNA or antigen in a respiratory specimen >90 d before collection of the cluster-associated specimen.
¶Persons who had underlying medical conditions associated with increased risk for severe COVID-19, including active cancer, autoimmune disease, cardiovascular disease, chronic kidney disease, chronic liver disease, chronic lung disease, current pregnancy, diabetes, solid organ or stem cell transplant, infection with HIV, and other immunocompromising conditions (13).
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1These authors contributed equally to this article.
2These senior authors contributed equally to this article.