Universal Polymerase Chain Reaction and Antibody Testing Demonstrate Little to No Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 in a Rural Community. (30th October 2020)

• Record Type: Journal Article
• Authors: Appa, Ayesha; Takahashi, Saki; Rodriguez-Barraquer, Isabel; Chamie, Gabriel; Sawyer, Aenor; Duarte, Elias; Hakim, Jill; Turcios, Keirstinne; Vinden, Joanna; Janson, Owen; Manglik, Aashish; Peluso, Michael J; Deeks, Steven G; Henrich, Timothy J; Torres, Leonel; Rodgers, Mary; Hackett, John; Chiu, Charles; Havlir, Diane; Greenhouse, Bryan
• Is Part Of: Open forum infectious diseases. Volume 8:Number 1(2021)
• Publication Date: 2020-10-30
• Subjects: COVID-19 -- rural population -- seroepidemiologic studies -- severe acute respiratory syndrome coronavirus 2; Communicable diseases -- Periodicals; Medical microbiology -- Periodicals; Infection -- Periodicals; 616.9
• DOI: 10.1093/ofid/ofaa531
• Languages: English
• ISSNs: 2328-8957

Abstract

Abstract: Background: Limited systematic surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the early months of the US epidemic curtailed accurate appraisal of transmission intensity. Our objective was to perform case detection of an entire rural community to quantify SARS-CoV-2 transmission using polymerase chain reaction (PCR) and antibody testing. Methods: We conducted a cross-sectional survey of SARS-CoV-2 infection in the rural town of Bolinas, California (population 1620), 4 weeks after shelter-in-place orders. Participants were tested between April 20 and 24, 2020. Prevalence by PCR and seroprevalence from 2 forms of antibody testing were performed in parallel (Abbott ARCHITECT immunoglobulin [Ig]G and in-house IgG enzyme-linked immunosorbent assay). Results: Of 1891 participants, 1312 were confirmed Bolinas residents (>80% community ascertainment). Zero participants were PCR positive. Assuming 80% sensitivity, it would have been unlikely to observe these results ( P < .05) if there were >3 active infections in the community. Based on antibody results, estimated prevalence of prior infection was 0.16% (95% credible interval [CrI], 0.02%–0.46%). The positive predictive value (PPV) of a positive result on both tests was 99.11% (95% CrI, 95.75%–99.94%), compared with PPV 44.19%–63.32% (95% CrI, 3.25%–98.64%) if 1 test was utilized. Conclusions: Four weeks after shelter-in-place, SARS-CoV-2 infection in a rural Northern California community was extremely rare. In this low-prevalence setting, use of 2 antibody tests increased seroprevalence estimate precision. This was one of the first community-wide studies to successfully implement synchronous PCR and antibody testing, particularly in a rural setting. Widespread testing remains an underpinning of effective disease control in conjunction with consistent uptake of public health measures.