Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort

Abstract Background A considerable amount of evidence demonstrates the potential of saliva in the diagnosis of COVID-19. Our aim was to determine the sensitivity of saliva versus swabs collected by healthcare workers (HCWs) and patients themselves to assess whether saliva detection can be offered as...

Full description

Bibliographic Details
Main Authors: Mitnala Sasikala, Yelamanchili Sadhana, Ketavarapu Vijayasarathy, Anand Gupta, Sarala Kumari Daram, Naveen Chander Reddy Podduturi, Duvvur Nageshwar Reddy
Format: Article
Language:English
Published: BMC 2021-07-01
Series:BMC Infectious Diseases
Subjects:
Online Access:https://doi.org/10.1186/s12879-021-06343-w
_version_ 1818450480912662528
author Mitnala Sasikala
Yelamanchili Sadhana
Ketavarapu Vijayasarathy
Anand Gupta
Sarala Kumari Daram
Naveen Chander Reddy Podduturi
Duvvur Nageshwar Reddy
author_facet Mitnala Sasikala
Yelamanchili Sadhana
Ketavarapu Vijayasarathy
Anand Gupta
Sarala Kumari Daram
Naveen Chander Reddy Podduturi
Duvvur Nageshwar Reddy
author_sort Mitnala Sasikala
collection DOAJ
description Abstract Background A considerable amount of evidence demonstrates the potential of saliva in the diagnosis of COVID-19. Our aim was to determine the sensitivity of saliva versus swabs collected by healthcare workers (HCWs) and patients themselves to assess whether saliva detection can be offered as a cost-effective, risk-free method of SARS-CoV-2 detection. Methods This study was conducted in a hospital involving outpatients and hospitalized patients. A total of 3018 outpatients were tested. Of these, 200 qRT-PCR-confirmed SARS-CoV-2-positive patients were recruited for further study. In addition, 101 SARS-CoV-2-positive hospitalized patients with symptoms were also enrolled in the study. From outpatients, HCWs collected nasopharyngeal swabs (NPS), saliva were obtained. From inpatients, HCWs collected swabs, patient-collected swabs, and saliva were obtained. qRT-PCR was performed to detect SARS-CoV-2 by TAQPATH assay to determine the sensitivity of saliva detection. Sensitivity, specificity and positive/negative predictive values (PPV, NPV) of detecting SARS-CoV-2 were calculated using MedCalc. Results Of 3018 outpatients (asymptomatic: 2683, symptomatic: 335) tested by qRT-PCR, 200 were positive (males: 140, females: 60; aged 37.9 ± 12.8 years; (81 asymptomatic, 119 symptomatic). Of these, saliva was positive in 128 (64%); 39 of 81 asymptomatic (47%),89 of 119 symptomatic patients (74.8%). Sensitivity of detection was 60.9% (55.4–66.3%, CI 95%), with a negative predictive value of 36%(32.9–39.2%, CI 95%).Among 101 hospitalized patients (males:65, females: 36; aged 53.48 ± 15.6 years), with HCW collected NPS as comparator, sensitivity of saliva was 56.1% (47.5–64.5, CI 95%), specificity 63.5%(50.4–75.3, CI95%) with PPV of 77.2% and NPV of 39.6% and that of self-swab was 52.3%(44–60.5%, CI95%), specificity 56.6% (42.3–70.2%, CI95%) with PPV 77.2% and NPV29.7%. Comparison of positivity with the onset of symptoms revealed highest detection in saliva on day 3 after onset of symptoms. Additionally, only saliva was positive in 13 (12.8%) hospitalized patients. Conclusion Saliva which is easier to collect than nasopharyngeal swab is a viable alternate to detect SARS-COV-2 in symptomatic patients in the early stage of onset of symptoms. Although saliva is currently not recommended for screening asymptomatic patients, optimization of collection and uniform timing of sampling might improve the sensitivity enabling its use as a screening tool at community level.
first_indexed 2024-12-14T20:51:59Z
format Article
id doaj.art-5b7a3f0463624a78b6a241babf454cfc
institution Directory Open Access Journal
issn 1471-2334
language English
last_indexed 2024-12-14T20:51:59Z
publishDate 2021-07-01
publisher BMC
record_format Article
series BMC Infectious Diseases
spelling doaj.art-5b7a3f0463624a78b6a241babf454cfc2022-12-21T22:47:48ZengBMCBMC Infectious Diseases1471-23342021-07-012111710.1186/s12879-021-06343-wComparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohortMitnala Sasikala0Yelamanchili Sadhana1Ketavarapu Vijayasarathy2Anand Gupta3Sarala Kumari Daram4Naveen Chander Reddy Podduturi5Duvvur Nageshwar Reddy6Department of Molecular Biology, Institute of Translational Research, Asian Healthcare Foundation, AIG HospitalsDepartment of Microbiology, AIG HospitalsDepartment of Molecular Biology, Institute of Translational Research, Asian Healthcare Foundation, AIG HospitalsDepartment of Critical Care Medicine, AIG HospitalsDepartment of Critical Care Medicine, AIG HospitalsDepartment of Critical Care Medicine, AIG HospitalsDepartment of Medical Gastroenterology, AIG HospitalsAbstract Background A considerable amount of evidence demonstrates the potential of saliva in the diagnosis of COVID-19. Our aim was to determine the sensitivity of saliva versus swabs collected by healthcare workers (HCWs) and patients themselves to assess whether saliva detection can be offered as a cost-effective, risk-free method of SARS-CoV-2 detection. Methods This study was conducted in a hospital involving outpatients and hospitalized patients. A total of 3018 outpatients were tested. Of these, 200 qRT-PCR-confirmed SARS-CoV-2-positive patients were recruited for further study. In addition, 101 SARS-CoV-2-positive hospitalized patients with symptoms were also enrolled in the study. From outpatients, HCWs collected nasopharyngeal swabs (NPS), saliva were obtained. From inpatients, HCWs collected swabs, patient-collected swabs, and saliva were obtained. qRT-PCR was performed to detect SARS-CoV-2 by TAQPATH assay to determine the sensitivity of saliva detection. Sensitivity, specificity and positive/negative predictive values (PPV, NPV) of detecting SARS-CoV-2 were calculated using MedCalc. Results Of 3018 outpatients (asymptomatic: 2683, symptomatic: 335) tested by qRT-PCR, 200 were positive (males: 140, females: 60; aged 37.9 ± 12.8 years; (81 asymptomatic, 119 symptomatic). Of these, saliva was positive in 128 (64%); 39 of 81 asymptomatic (47%),89 of 119 symptomatic patients (74.8%). Sensitivity of detection was 60.9% (55.4–66.3%, CI 95%), with a negative predictive value of 36%(32.9–39.2%, CI 95%).Among 101 hospitalized patients (males:65, females: 36; aged 53.48 ± 15.6 years), with HCW collected NPS as comparator, sensitivity of saliva was 56.1% (47.5–64.5, CI 95%), specificity 63.5%(50.4–75.3, CI95%) with PPV of 77.2% and NPV of 39.6% and that of self-swab was 52.3%(44–60.5%, CI95%), specificity 56.6% (42.3–70.2%, CI95%) with PPV 77.2% and NPV29.7%. Comparison of positivity with the onset of symptoms revealed highest detection in saliva on day 3 after onset of symptoms. Additionally, only saliva was positive in 13 (12.8%) hospitalized patients. Conclusion Saliva which is easier to collect than nasopharyngeal swab is a viable alternate to detect SARS-COV-2 in symptomatic patients in the early stage of onset of symptoms. Although saliva is currently not recommended for screening asymptomatic patients, optimization of collection and uniform timing of sampling might improve the sensitivity enabling its use as a screening tool at community level.https://doi.org/10.1186/s12879-021-06343-wSARS-COV-2SalivaHealthcare workerNasopharyngeal swab
spellingShingle Mitnala Sasikala
Yelamanchili Sadhana
Ketavarapu Vijayasarathy
Anand Gupta
Sarala Kumari Daram
Naveen Chander Reddy Podduturi
Duvvur Nageshwar Reddy
Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort
BMC Infectious Diseases
SARS-COV-2
Saliva
Healthcare worker
Nasopharyngeal swab
title Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort
title_full Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort
title_fullStr Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort
title_full_unstemmed Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort
title_short Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort
title_sort comparison of saliva with healthcare workers and patient collected swabs in the diagnosis of covid 19 in a large cohort
topic SARS-COV-2
Saliva
Healthcare worker
Nasopharyngeal swab
url https://doi.org/10.1186/s12879-021-06343-w
work_keys_str_mv AT mitnalasasikala comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort
AT yelamanchilisadhana comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort
AT ketavarapuvijayasarathy comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort
AT anandgupta comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort
AT saralakumaridaram comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort
AT naveenchanderreddypodduturi comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort
AT duvvurnageshwarreddy comparisonofsalivawithhealthcareworkersandpatientcollectedswabsinthediagnosisofcovid19inalargecohort