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. 2021 Jul 1;4(7):e2115980.
doi: 10.1001/jamanetworkopen.2021.15980.

Asymptomatic and Symptomatic COVID-19 Infections Among Health Care Personnel Before and After Vaccination

Shruti K Gohil  1   2 , Keith Olenslager  1 , Kathleen A Quan  1 , Cyrus K Dastur  3 , Nasim Afsar  4 , Wayne Chang  5 , Susan S Huang  1   2
Affiliations

Asymptomatic and Symptomatic COVID-19 Infections Among Health Care Personnel Before and After Vaccination

Shruti K Gohil et al. JAMA Netw Open. .

Abstract

This cohort study investigates asymptomatic and symptomatic COVID-19 case rates before and after the initial vaccine rollout among health care personnel in Orange County, California.

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Conflict of interest statement

Conflict of Interest Disclosures: None reported.

Figures

Figure 1.
Figure 1.. Daily Counts of COVID-19 Incident Cases Among Health Care Personnel in Orange County and University of California Irvine (UCI) Health
COVID-19 cases among health care personnel declined after vaccination and in advance of countywide reductions. Data displayed as rolling 7-day averages (means) between November 8, 2020, to March 14, 2021.
Figure 2.
Figure 2.. Percentage of Health Care Personnel Who Tested Positive for COVID-19 Using the Asymptomatic Testing Pathway
Most health care personnel who tested positive using the asymptomatic testing pathway reported symptoms consistent with COVID-19 (81% [34 of 42]). Asymptomatic cases declined to 0 after vaccination.
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