Severe Acute Respiratory Syndrome Coronavirus 2 detection in induced sputum of asthmatic patients using saliva sampling device

Since the beginning of the severe acute respiratory syndrome coronavirus 2 pandemic, the potential contamination of the induced sputum obtained from asthmatic patients in routine is a question of concern. The goal of this study was to assess this contamination using a saliva sample collection device. One hundred seventy-five sputum samples of asthmatic patients without fever were tested. We did not identify any positive PCR on sputum samples from asthmatic patients reporting chronic/episodic respiratory symptoms similar to what is seen in case of COVID-19. This technique was useful to evaluate the contamination of sputum samples generated during the pandemic. ### Competing Interest Statement JG reports personal fees for advisory board, work and lectures from Boehringer Ingelheim, Janssens, GSK, Roche and Chiesi, non-financial support for meeting attendance from Chiesi, Roche, Boehringer Ingelheim and Janssens. He is in the permanent SAB of Radiomics (Oncoradiomics SA) for the SALMON trial without any specific consultancy fee for this work. He is co-inventor of one issued patent on radiomics licensed to Radiomics (Oncoradiomics SA). He confirms that none of the above entities or funding was involved in the preparation of this work. LG and FB report a patent on the saliva sampling device. This device was patented (EP20186086.3) and produced by Diagenode (Seraing, Belgium) under a commercial agreement with the University of Liege. This does not alter the adherence to a journal policy on sharing data and materials. RL reports grants from GSK, grants and personal fees from AZ, Novartis, Chiesi. CM, SG, NB, RB, FS, MH, FG, VP, EDV, MSN and FM report no conflicts of interest. ### Funding Statement This research did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors. The authors would like to thank Uliege/CHU Liege and the GIGA viral vector platform and Diagnostic COVID-19 platform Uliege-Cellular and molecular immunology laboratory of Uliege. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Ethics committee of CHU Liege gave approval for this work (CHU 2009/161 and 2020/107). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors * ATS : American Thoracic Society BSL : Biosafety level COVID-19 : Coronavirus infectious disease 19 Ct : Cycle threshold ERS : European Respiratory Society ICU : Intensive care unit OCS : Oral corticosteroids ORF1ab : Open reading frame 1a region N : Nucleoprotein RNA : Ribonucleic acid SARS-CoV-2 : Severe Acute Respiratory Syndrome Coronavirus 2 S : Spike protein gene