TY - JOUR
T1 - Surveillance testing using salivary RT-PCR for SARS-CoV-2 in managed quarantine facilities in Australia
T2 - A laboratory validation and implementation study
AU - Jenney, Adam
AU - Chibo, Doris
AU - Batty, Mitch
AU - Druce, Julian
AU - Melvin, Robert
AU - Stewardson, Andrew
AU - Dennison, Amanda
AU - Symes, Sally
AU - Kinsella, Paul
AU - Tran, Thomas
AU - Mackenzie, Charlene
AU - Johnson, Douglas
AU - Thevarajan, Irani
AU - McGrath, Christian
AU - Matlock, Amelia
AU - Prestedge, Jacqueline
AU - Gooey, Megan
AU - Roney, Janine
AU - Bobbitt, Joanne
AU - Yallop, Sarah
AU - Catton, Mike
AU - Williamson, Deborah A.
N1 - Funding Information:
We acknowledge the support all diagnostic laboratories involved in this project. We acknowledge the work done by COVID Quarantine Victoria and Alfred Health and thank the staff and patients who contributed to this study.
Publisher Copyright:
© 2022 The Author(s)
PY - 2022/9
Y1 - 2022/9
N2 - Background: Regular repeat surveillance testing is a strategy to identify asymptomatic individuals with SARS-CoV-2 infections in high-risk work settings to prevent onward community transmission. Saliva sampling is less invasive compared to nasal/oropharyngeal sampling, thus making it suitable for regular testing. In this multi-centre evaluation, we aimed to validate RT-PCR using salivary swab testing of SARS-CoV-2 for large-scale surveillance testing and assess implementation amongst staff working in the hotel quarantine system in Victoria, Australia. Methods: A multi-centre laboratory evaluation study was conducted to systematically validate the in vitro and clinical performance of salivary swab RT-PCR for implementation of SARS-CoV-2 surveillance testing. Analytical sensitivity for multiple RT-PCR platforms was assessed using a dilution series of known SARS-CoV-2 viral loads, and assay specificity was examined using a panel of viral pathogens other than SARS-CoV-2. In addition, we tested capacity for large-scale saliva testing using a four-sample pooling approach, where positive pools were subsequently decoupled and retested. Regular, frequent self-collected saliva swab RT-PCR testing was implemented for staff across fourteen quarantine hotels. Samples were tested at three diagnostic laboratories validated in this study, and results were provided back to staff in real-time. Findings: The agreement of self-collected saliva swabs for RT-PCR was 84.5% (95% CI 68.6 to 93.8) compared to RT-PCR using nasal/oropharyngeal swab samples collected by a healthcare practitioner, when saliva samples were collected within seven days of symptom onset. Between 7th December 2020 and 17th December 2021, almost 500,000 RT-PCR tests were performed on saliva swabs self-collected by 102 staff working in quarantine hotels in Melbourne. Of these, 20 positive saliva swabs were produced by 13 staff (0.004%). The majority of staff that tested positive occurred during periods of community transmission of the SARS-CoV-2 Delta variant. Interpretation: Salivary RT-PCR had an acceptable level of agreement compared to standard nasal/oropharyngeal swab RT-PCR within early symptom onset. The scalability, tolerability and ease of self-collection highlights utility for frequent or repeated testing in high-risk settings, such as quarantine or healthcare environments where regular monitoring of staff is critical for public health, and protection of vulnerable populations. Funding: This work was funded by the Victorian Department of Health.
AB - Background: Regular repeat surveillance testing is a strategy to identify asymptomatic individuals with SARS-CoV-2 infections in high-risk work settings to prevent onward community transmission. Saliva sampling is less invasive compared to nasal/oropharyngeal sampling, thus making it suitable for regular testing. In this multi-centre evaluation, we aimed to validate RT-PCR using salivary swab testing of SARS-CoV-2 for large-scale surveillance testing and assess implementation amongst staff working in the hotel quarantine system in Victoria, Australia. Methods: A multi-centre laboratory evaluation study was conducted to systematically validate the in vitro and clinical performance of salivary swab RT-PCR for implementation of SARS-CoV-2 surveillance testing. Analytical sensitivity for multiple RT-PCR platforms was assessed using a dilution series of known SARS-CoV-2 viral loads, and assay specificity was examined using a panel of viral pathogens other than SARS-CoV-2. In addition, we tested capacity for large-scale saliva testing using a four-sample pooling approach, where positive pools were subsequently decoupled and retested. Regular, frequent self-collected saliva swab RT-PCR testing was implemented for staff across fourteen quarantine hotels. Samples were tested at three diagnostic laboratories validated in this study, and results were provided back to staff in real-time. Findings: The agreement of self-collected saliva swabs for RT-PCR was 84.5% (95% CI 68.6 to 93.8) compared to RT-PCR using nasal/oropharyngeal swab samples collected by a healthcare practitioner, when saliva samples were collected within seven days of symptom onset. Between 7th December 2020 and 17th December 2021, almost 500,000 RT-PCR tests were performed on saliva swabs self-collected by 102 staff working in quarantine hotels in Melbourne. Of these, 20 positive saliva swabs were produced by 13 staff (0.004%). The majority of staff that tested positive occurred during periods of community transmission of the SARS-CoV-2 Delta variant. Interpretation: Salivary RT-PCR had an acceptable level of agreement compared to standard nasal/oropharyngeal swab RT-PCR within early symptom onset. The scalability, tolerability and ease of self-collection highlights utility for frequent or repeated testing in high-risk settings, such as quarantine or healthcare environments where regular monitoring of staff is critical for public health, and protection of vulnerable populations. Funding: This work was funded by the Victorian Department of Health.
KW - COVID-19
KW - RT-PCR
KW - Saliva
KW - SARS-CoV-2
KW - Surveillance testing
UR - http://www.scopus.com/inward/record.url?scp=85133900097&partnerID=8YFLogxK
U2 - 10.1016/j.lanwpc.2022.100533
DO - 10.1016/j.lanwpc.2022.100533
M3 - Article
C2 - 35821908
AN - SCOPUS:85133900097
SN - 2666-6065
VL - 26
JO - The Lancet Regional Health - Western Pacific
JF - The Lancet Regional Health - Western Pacific
M1 - 100533
ER -