Surveillance testing using salivary RT-PCR for SARS-CoV-2 in managed quarantine facilities in Australia: A laboratory validation and implementation study.

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.

Implementation of a Nationwide Knowledge-Based COVID-19 Contact Tracing Training Program, 2020.

In the United States, the public health response to control COVID-19 required rapid expansion of the contact tracing workforce from approximately 2200 personnel prepandemic to more than 100 000 during the pandemic. We describe the development and implementation of a free nationwide training course for COVID-19 contact tracers that launched April 28, 2020, and summarize participant characteristics and evaluation findings through December 31, 2020. Uptake of the online asynchronous training was substantial: 90 643 registrants completed the course during the first 8 months. In an analysis of a subset of course participants (n = 13 697), 7724 (56.4%) reported having no prepandemic public health experience and 7178 (52.4%) reported currently serving as case investigators, contact tracers, or both. Most participants who completed a course evaluation reported satisfaction with course utility (94.8%; 59 497 of 62 753) and improved understanding of contact tracing practice (93.0%; 66 107 of 71 048). These findings suggest that the course successfully reached the intended audience of new public health practitioners. Lessons learned from this implementation indicate that an introductory course level is appropriate for a national knowledge-based training that aims to complement jurisdiction-specific training. In addition, offering a range of implementation options can promote course uptake among public health agency staff. This course supported the emerging needs of the public health practice community by training a workforce to fill an important gap during the COVID-19 pandemic and could serve as a feasible model for enhancing workforce knowledge for future and ongoing public health threats.