• Abderrezak GHIDOUCHE 1Faculté des Sciences de la Nature et de la Vie, Université de Bejaia, Bejaia, Algérie. 2Laboratoire de Génie Biologique des Cancers, Université de Bejaia, Bejaia, Algérie.
  • Sarah HALLOUCHE 2Laboratoire de Génie Biologique des Cancers, Université de Bejaia, Bejaia, Algérie. 3Faculté de Médecine, Université de Bejaia, Bejaia, Algérie.
  • Djida AIT-ALI 1Faculté des Sciences de la Nature et de la Vie, Université de Bejaia, Bejaia, Algérie. 2Laboratoire de Génie Biologique des Cancers, Université de Bejaia, Bejaia, Algérie.
  • Lila BOUDRAHEM-HANNOU 3Faculté de Médecine, Université de Bejaia, Bejaia, Algérie. 4Service des maladies infectieuses, CHU de Bejaia, Algérie.
  • Hamid NOURI Laboratoire de Microbiologie Appliquée, Université de Bejaia, Bejaia, Algérie. Faculté des Sciences de la Nature et de la Vie, Université de Bejaia, Bejaia, Algérie.
  • Souhil TLIBA Laboratoire de Génie Biologique des Cancers, Université de Bejaia, Bejaia, Algérie. Service de Neurochirurgie, CHU de Blida, Algérie
  • Idir BITAM Ecole Supérieure en Sciences de l'Aliment et des Industries Agroalimentaires (ESSAIA), El Harrach, Alger, Algérie. Aix Marseille Univ, IRD, VITROME, IHU Méditerranée Infection, Marseille, France.
  • Adel AMIROUCHE Uiversity of BEJAIA



SARS-CoV-2, Diagnostic, Nasopharyngeal swab, Saliva, RT-PCR.


Background : Various detection methods, based on specific nucleotide sequences of SARS-CoV-2, were rapidly developed and used as emergency laboratory applications. The most common diagnostic method for detecting SARS-CoV-2 infection is real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR).

Aims: Here, we carried out to assess the sensitivity and specificity of using saliva self-collected from adult and pediatric patients, as a biological sample for RT-PCR diagnosis.

Methods: We compared the sensitivity and specificity of RT-qPCR from 85 samples of adult and pediatric patient, including nasopharyngeal swabs (NPS) and saliva.

Results: Our RT-qPCR results provide that saliva samples showed the highest sensitivity followed by a nasopharyngeal swab for symptomatic as well as for asymptomatic adult patients. On the other hand, samples from symptomatic patients showed a higher sensitivity as compared to asymptomatic patients, while a cycle threshold (Ct) value exhibited a higher sensitivity as compared to higher Ct value. Together, including symptomatic and asymptomatic subjects, the overall agreement between the saliva sample and the nasopharyngeal is about 84%.

Conclusion: The sensitivity of saliva samples remains acceptable; it may still be a viable option in locations where laboratory facilities are lacking for diagnostic purposes in the early phase of the disease.


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