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. 2021 May 24:jiab281. doi: 10.1093/infdis/jiab281

Seroprevalence of SARS-CoV-2 Among Skilled Nursing Facility Residents and Staff Members — Los Angeles County, August–September 2020

Jason H Malenfant 1,2, Michelle Eslami 3, Bonnie L Dao 2, Leo Moore 2, Nicole Green 4, David Silver 3, Kelsey OYong 2, Ashutosh Ruparelia 2, Rebecca Fisher 2, Julia S Wood 2, Mohammad Faisal 2, Faith Washburn 2, Steve Shvartsblat 2, Mirna P Jewell 2, Tiffany Romo 2, Chelsea Foo 2, Angela Salazar 2, Shobita Rajagopalan 2, Zachary A Rubin 2, Prabhu Gounder 2,
PMCID: PMC8243593  PMID: 34031692

Abstract

Background

The prevalence of current/past coronavirus disease 2019 (COVID-19) in skilled nursing facility (SNF) residents is unknown because of asymptomatic infection and constrained testing capacity early in the pandemic. We conducted a seroprevalence survey (SPS) to determine a more comprehensive prevalence of past COVID-19 in Los Angeles County SNF residents and staff members.

Methods

We recruited participants from 24 facilities; participants were requested to submit a nasopharyngeal (NP) swab for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR testing and serum for detection of SARS-CoV-2 antibodies. All participants were cross-referenced with our surveillance database to identify persons with prior positive SARS-CoV-2 results.

Results

From August 18 to September 24, 2020, we enrolled 3,305 participants (1,340 residents and 1,965 staff members). Among 856 residents providing serum, 362 (42%) had current/past SARS-CoV-2 infection. Of the 346 serology positive residents, 199 (58%) did not have a documented prior positive SARS-CoV-2 PCR result. Among 1,806 staff members providing serum, 454 (25%) had current/past SARS-CoV-2 infection. Of the 447 serology positive staff members, 353 (79%) did not have a documented prior positive SARS-CoV-2 PCR result.

Conclusions

Past testing practices and policies missed a substantial number of SARS-CoV-2 infections in SNF residents and staff members.

Keywords: COVID-19, SARS-CoV-2, Seroprevalence, Skilled nursing facilities

Supplementary Material

jiab281_suppl_Supplementary_Materials

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

jiab281_suppl_Supplementary_Materials

Articles from The Journal of Infectious Diseases are provided here courtesy of Oxford University Press

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