tetano
Editor, Senior Moderator
Open Forum Infect Dis
. 2020 Oct 30;8(1)
faa531.
doi: 10.1093/ofid/ofaa531. eCollection 2021 Jan.
Universal Polymerase Chain Reaction and Antibody Testing Demonstrate Little to No Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 in a Rural Community
Ayesha Appa[SUP] 1 [/SUP], Saki Takahashi[SUP] 1 [/SUP], Isabel Rodriguez-Barraquer[SUP] 1 [/SUP], Gabriel Chamie[SUP] 1 [/SUP], Aenor Sawyer[SUP] 1 [/SUP], Elias Duarte[SUP] 1 [/SUP], Jill Hakim[SUP] 1 [/SUP], Keirstinne Turcios[SUP] 1 [/SUP], Joanna Vinden[SUP] 2 [/SUP], Owen Janson[SUP] 1 [/SUP], Aashish Manglik[SUP] 1 [/SUP], Michael J Peluso[SUP] 1 [/SUP], Steven G Deeks[SUP] 1 [/SUP], Timothy J Henrich[SUP] 1 [/SUP], Leonel Torres[SUP] 1 [/SUP], Mary Rodgers[SUP] 3 [/SUP], John Hackett[SUP] 3 [/SUP], Charles Chiu[SUP] 1 [/SUP], Diane Havlir[SUP] 1 [/SUP], Bryan Greenhouse[SUP] 1 4 [/SUP]
Affiliations
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.
Keywords: COVID-19; rural population; seroepidemiologic studies; severe acute respiratory syndrome coronavirus 2.
. 2020 Oct 30;8(1)
doi: 10.1093/ofid/ofaa531. eCollection 2021 Jan.
Universal Polymerase Chain Reaction and Antibody Testing Demonstrate Little to No Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 in a Rural Community
Ayesha Appa[SUP] 1 [/SUP], Saki Takahashi[SUP] 1 [/SUP], Isabel Rodriguez-Barraquer[SUP] 1 [/SUP], Gabriel Chamie[SUP] 1 [/SUP], Aenor Sawyer[SUP] 1 [/SUP], Elias Duarte[SUP] 1 [/SUP], Jill Hakim[SUP] 1 [/SUP], Keirstinne Turcios[SUP] 1 [/SUP], Joanna Vinden[SUP] 2 [/SUP], Owen Janson[SUP] 1 [/SUP], Aashish Manglik[SUP] 1 [/SUP], Michael J Peluso[SUP] 1 [/SUP], Steven G Deeks[SUP] 1 [/SUP], Timothy J Henrich[SUP] 1 [/SUP], Leonel Torres[SUP] 1 [/SUP], Mary Rodgers[SUP] 3 [/SUP], John Hackett[SUP] 3 [/SUP], Charles Chiu[SUP] 1 [/SUP], Diane Havlir[SUP] 1 [/SUP], Bryan Greenhouse[SUP] 1 4 [/SUP]
Affiliations
- PMID: 34109255
- PMCID: PMC7665736
- DOI: 10.1093/ofid/ofaa531
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.
Keywords: COVID-19; rural population; seroepidemiologic studies; severe acute respiratory syndrome coronavirus 2.