Saliva: an important alternative for screening and monitoring of COVID-19 in children

Abstract

The increasing number of cases of COVID-19 worldwide poses challenges to healthcare systems not only in effectively identifying individuals positive for SARS-CoV-2, but also in isolating cases to minimise contagion in early diagnosing more severe cases that will need hospitalization. Less-invasive collection methods are indispensable in a pandemic scenario as large-scale tests are necessary to understand the actual evolution of contagion in different populations, thus enabling decision-making based on scientific evidence. Saliva has been shown to be an alternative for diagnosing viral infections as this biological fluid can be easily and quickly collected without using specific devices and causing less discomfort during collection, which is an important factor for use in children. Despite the smaller percentage of severe cases of COVID-19 among children, they seem to play an important role in the contagion as they have the same potential of transmission as that of adults. Knowing the evolution of COVID-19 pandemic in children is extremely important, mainly regarding the changing in rules of social distancing, such as reopening schools and recreational activities spaces. In addition, countless cases of a severe multi-systemic inflammatory syndrome that shares clinical and laboratory features with Kawasaki's disease have been recently related to SARS-CoV-2 infections in children, adolescents and young adults. In view of this scenario, the aim of this study was to present saliva as an alternative for seeking diagnostic and prognostic markers of COVID-19 in children, including adequate sample collection techniques for different age groups.

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

“…Massive testing is one of the most effective strategies for preventing COVID-19 transmission by allowing early identification of cases and decision-making based on the pandemic's behaviour 1 . Nasopharyngeal swab (NPS) is the standard sample for molecular test, which causes much discomfort and possible cross-contamination during the collection 1,2 . Therefore, a trained healthcare professional is required for performing this procedure 1,3 .…”

“…Saliva has been shown to be a reliable, safe diagnostic fluid for detection of SARS-CoV-2, with a sensitivity ranging from 80-100% compared to NPS in adult population 1,3,4 . In paediatrics, the use of saliva has clear advantages because the collection of this fluid is less invasive, thus reducing the discomfort and allowing self-collection 2 .…”

Sinais e sintomas de manifestações orais e cutâneas em crianças com COVID-19: revisão narrativa

“…Vários estudos, de diversos países, relatam sintomas consistentes com infecção por SARS-CoV-2 nos dias e semanas anteriores ao aparecimento de frieiras ou contato com pessoas que apresentaram esses sintomas (Andina et al, 2021;Docampo-Simon et al, 2020;Khalili et al, 2021;Li et al, 2020;Singh, Kaur, Singh, & Sen, 2021). Foi também relatado nos artigos, que a exposição de crianças ao SARS-CoV-2 resulta no desenvolvimento da Síndrome Inflamatória Multissistêmica (Kabeerdoss et al, 2021;Santos et al, 2020). O diagnóstico é baseado em critérios clínicos que incluem febre por pelo menos cinco dias e presença de algumas características clinicas como: injeção conjuntival bilateral; linfadenopatia cervical; alterações da mucosa oral; erupções cutâneas polimórficas; edema ou vermelhidão das extremidades e exclusão de diagnósticos alternativos.…”

“…Ao contrário dos adultos, as crianças com a COVID-19 apresentam sintomas clínicos mais brandos, e em muitos casos, assintomáticos. Porém, mesmo nestas condições não impede de transmitir o vírus (Mehta et al, 2020;Santos et al, 2020).…”

A narrative review of exploring potential salivary biomarkers in respiratory diseases: still on its way

“…It has been reported that influenza virus A, Ebola virus, Cytomegalovirus, and Herpes simplex virus could be identified in salivary samples (68). During the pandemic of COVID-19, testing of saliva samples for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) attracted a lot of attention because of the ease associated with self-collection and a decrease in the risk of exposure associated with the collection of nasopharyngeal or oropharyngeal samples by healthcare workers (39,40,(69)(70)(71)(72)(73)(74). The coincidence rate for the detection of SARS-CoV-2 between salivary samples and nasopharyngeal swabs was 91.7~100% (39,40).…”