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Background: Salivary detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been proposed as an alternative to nasopharyngeal or oropharyngeal swab testing. Our group previously published a study demonstrating that both testing methods identified SARS-CoV-2 using polymerase chain reaction (PCR)-based detection methodology. We therefore conducted a follow-up study using antibody testing to evaluate the accuracy of saliva versus swabs for COVID-19 detection and the durability of antibody response., Methods: Venous blood samples were collected from consenting participants and the presence of serum antibodies for SARS-CoV-2 was evaluated on a large, automated immunoassay platform by the Roche anti-SARS-CoV-2 qualitative assay (Roche Diagnostics, Laval Quebec). Individuals with a serum antibody cut-off index (COI) ≥ 1.0 were considered positive., Results: In asymptomatic and mildly symptomatic patients with a previously positive standard swab and/or saliva SARS-CoV-2 PCR-test, 42 demonstrated antibodies with 13 patients positive by swab alone, and 8 patients positive by saliva alone., Conclusions: Despite their status as 'current standard' for COVID-19 testing, these findings highlight limitations of PCR-based tests.

Background: Human papillomavirus (HPV) is an important cause of head and neck squamous cell carcinoma (HNSCC), especially in young people. These tumours overexpress p16 and respond well to treatment. The rapid detection of HPV in patients with HNSCC may expedite treatment when p16 status is not immediately available., Methods: Saliva-based DNA collection kits and nested polymerase chain reaction (PCR) were used to determine the HPV status of 62 individuals with biopsy-proven HNSCC. Immunohistochemistry was used to determine tumour p16 status., Results: A total of 62 patients were included in the study. Twenty-nine samples (47%) were positive for HPV DNA, the majority of which were high risk (HR) subtypes (79%). Patients who tested positive for HR HPV were more likely to have a tumour arising in the oropharynx compared to a non-oropharyngeal site (74 vs 26%; p = 0.003). A positive HR HPV saliva assay was 100% specific (95% CI 59-100%) and had a 100% positive predictive value (95% CI 75-100%) for a p16 positive tumour arising in the oropharynx. In contrast, a negative HR HPV assay had a 96% negative predictive value (95% CI 80-100%) for tumours arising in a non-oropharyngeal site. Independent of site, the saliva assay had a sensitivity of 77% (95% CI 54-91%) and a specificity of 94% (95% CI 77-99%), respectively, for a p16 positive tumour., Conclusion: We show that a saliva based assay is an effective method for detecting HPV in patients with HNSCC and that a positive HR HPV test is highly specific for p16 positive tumours arising in the oropharynx. This simple and rapid test could be used in cases where a biopsy of the primary tumour is not readily available.

Objective: To determine the persistence of human papillomavirus (HPV) infection following treatment of HPV-positive oropharyngeal squamous cell carcinoma (HPV + OPSCC). Methods: A cross-sectional study was undertaken at The Ottawa Hospital (Ottawa, ON, Canada), a tertiary academic hospital and regional cancer center. Adult patients who were diagnosed with HPV + OPSCC between the years of 2014 and 2016 and treated with curative intent, and who were alive and willing to consent were eligible for inclusion. A saliva assay was used to test for the presence of HPV DNA in a random sample of patients. qPCR was used to amplify DNA from saliva samples. Results: Saliva samples were obtained from 69 patients previously treated with HPV + OPSCC. All patients had a minimum of 2 years of follow-up. 5 patients tested positive for HPV: 2 were positive for HPV-16, 2 for HPV-18, and 1 "other" HPV type. No patient in our study cohort had suffered recurrence post-treatment. Conclusions: This study is the first to demonstrate the prevalence of persistent oncogenic HPV DNA in saliva following treatment for HPV + OPSCC. This prevalence appears to be low, despite the fact that persistent HPV infection is a precursor for the development of HPV + OPSCC. This finding raises questions about what factors influence the clearance or persistence of HPV DNA in saliva after treatment for HPV + OPSCC, and may add to our understanding about the longitudinal effects of HPV infection in these cancers. [ABSTRACT FROM AUTHOR]

Background: Saliva sampling is a promising alternative to nasopharyngeal swabs for SARS-CoV-2 testing, but acceptability data is lacking. We characterize the acceptability of saliva sampling and nasopharyngeal swabs for primary decision makers and their children after experiencing both testing modalities. Methods: We administered a cross-sectional survey to participants aged 6-to-17 years and their primary decision makers at an Ottawa community COVID-19 testing centre in March 2021. Included were participants meeting local guidelines for testing. Excluded were those identified prior to participation as having inability to complete the consent, sampling, or survey process. Acceptability in multiple hypothetical scenarios was rated using a 5-point Likert scale. Pain was measured using the Faces Pain Scale—Revised (FPS-R). Preference for testing was assessed with direct binary questions. Results: 48 participants and 48 primary decision makers completed the survey. Nasopharyngeal swab acceptability differed between scenarios, ranging 79% [95%CI: 66, 88] to 100% [95%CI: 95, 100]; saliva sampling acceptability was similar across scenarios, ranging 92% [95%CI: 82, 97] to 98% [95%CI: 89, 99]. 58% of youth described significant pain with nasopharyngeal swabbing, versus none with saliva sampling. 90% of children prefer saliva sampling. 66% of primary decision makers would prefer nasopharyngeal swabbing if it were 10% more sensitive. Conclusion: Though youth prefer saliva sampling over nasopharyngeal swabs, primary decision makers present for testing remain highly accepting of both. Acceptance of nasopharyngeal swabs, however, varies with the testing indication and is influenced by perceived test accuracy. Understanding factors that influence sampling acceptance will inform more successful testing strategies. [ABSTRACT FROM AUTHOR]