SARS-CoV2 (COVID-19) Diagnosis in Human Saliva by MALDI-TOF MS Profiling

Since March 2020, SARS-CoV2 virus (nCoV19; COVID-19) is considered pandemic. Its high rate of spread and infection in the human population and the lack of effective and validated treatment have led the authorities of several countries to confine their populations to slow the spread of COVID-19. As part of the management of this health crisis, the screening of individuals is essential in order to isolate "infected cases". These screening tests are currently performed on nasopharyngeal swabs using RT-PCR for the detection of viral RNA. Although sensitive and specific, these tests remain relatively long (2-5 hours), expensive and the strong international demand for nucleic extraction kits and enzymes are factors limiting the implementation of widespread screening (problem of supply of swabs, molecular biology consumables). In order to prevent the risks of a shortage of screening means, we propose to develop an innovative alternative strategy, PCR-free, based on the detection of specific protein signatures in human saliva by MALDI-TOF MS profiling. MALDI-TOF MS profiling is a method used in routine diagnostics by microbiology laboratories for the identification of microorganisms. MALDI-TOF MS profiling has been successfully used to classify individuals according to their infectious status (oral pathologies) based on the analysis of their saliva, but also as a tool for the identification of respiratory viruses from cell culture supernatants. In addition, we have expertise and skills in the field of MALDI-TOF MS profiling and have implemented new strategies to improve the quality of profiles and their analysis, particularly in the context of entomological and vector identification projects. Finally, recent Chinese studies have reported that COVID-19 was detectable in saliva by RT-PCR. The main objective of this study is to develop a test based on the MALDI-TOF profiling method to detect individuals infected with SARS-CoV2 from saliva sample.