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 - 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
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 -