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Volume 27, Number 11—November 2021

Probability-Based Estimates of Severe Acute Respiratory Syndrome Coronavirus 2 Seroprevalence and Detection Fraction, Utah, USA

Matthew H. SamoreComments to Author , Adam Looney, Brian Orleans, Tom Greene, Nathan Seegert, Julio C. Delgado, Angela Presson, Chong Zhang, Jian Ying, Yue Zhang, Jincheng Shen, Patricia Slev, Maclean Gaulin, Mu-Jeung Yang, Andrew T. Pavia, and Stephen C. Alder
Author affiliations: Veterans Affairs Salt Lake City Health Care System, Salt Lake City, Utah, USA (M.H. Samore); University of Utah, Salt Lake City (M.H. Samore, A. Looney, B. Orleans, T. Greene, N. Seegert, J.C. Delgago, A. Presson, C. Zhang, J. Ying, Y. Zhang, J. Shen, P. Slev, M. Gaulin, M.-J. Yang, A.T. Pavia, S.C. Alder)

Main Article

Table 4

Relationship between COVID-19 exposures and serologic results of participants in a study of SARS-CoV-2 seroprevalence, Utah, USA*

Exposures Total No. (%) seronegative, n = 8,019 No. (%) seropositive, n = 89 % Adjusted seroprevalence (95% CI)†
Contact with diagnosed COVID-19 case
334 (92.8)
26 (7.2)
8.5 (3.3–19.5)
Participant’s relationship with contact
Family member 97 83 (85.6) 14 (14.4) 14.8 (4.0–40.8)
Friend 42 38 (90.5) 4 (9.5) 14.0
Healthcare worker‡ 38 38 (100) 0 (0) 0.0
Coworker 105 102 (97.1) 3 (2.9) 3.4
73 (93.6)
5 (6.4)
3.1 (0.3–12.9)
Reside in household with >1 seropositive person 123 100 (81.3) 23 (18.7) 24.9 (10.5–48.7)

*COVID-19, coronavirus disease; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2. †Adjusted for sampling design and test sensitivity (0.83) and specificity (0.996). Confidence intervals are omitted for subgroups with fewer than 5 seropositive persons. ‡Participant reported that their exposure was related to their work as a healthcare worker.

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Page created: August 05, 2021
Page updated: October 19, 2021
Page reviewed: October 19, 2021
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