Saliva as a Reliable Sample for COVID-19 Diagnosis in Paediatric Patients

Saliva has been described a less invasive and easy to handle sample, compared to nasopharyngeal swabs (NPS), in the diagnosis of COVID-19 in adults. Although the advantages of using saliva is still more evident in paediatric patients, little is now about its sensitivity in this group. The aim of this study was to compare the performance of saliva to that of NPS in the detection of SARS-CoV-2 in paediatric patients with mild symptoms. This study evaluated saliva samples from children with suspected COVID-19 who attended public healthcare services of Araraquara, São Paulo, Brazil. Children were asked to spit into a sterile container for collection of about 1ml of saliva after the NPS collection. SARS-COV-2 detection was performed by using the Altona RealStar® SARS-CoV-2 RT-PCR Kit 1.0. The sample consisted of 50 patients, in which 27 were girls (54%) and 23 were boys (46%). Ten were positive for SARS-CoV-2 in at least one sample collected. The mean age was 10.24 ± 3.52 years old and saliva was collected after 4.76 ± 1.31 days from the symptoms. Saliva and NPS have showed the same performance in the SARS-CoV-2 detection (k = 0.865, P < 0.001). In conclusion, saliva is a reliable alternative sample for COVID-19 diagnosis in paediatric population.