Detection of airborne respiratory viruses in pediatric patient rooms in Guangzhou, China

Background Despite the controversy of aerosol transmission for different respiratory viruses, there are few direct comparisons. Respiratory virus detection in the air can inform transmission risk assessment in healthcare settings. We aimed to identify five common respiratory viruses in the air in pediatric patient rooms. Methods We sampled air with two-stage cyclone samplers continuously for 4 hours in 5-bed pediatric patient rooms in a tertiary hospital in China. Respiratory virus RNA/DNA recovered in the air were quantified by PCR. Results We conducted air sampling on 44 occasions from December 2017 through January 2020, and identified 24, 18, 16, 4 and 8 occasions which had ≥1 patient in the room tested positive for respiratory syncytial virus (RSV), adenovirus (AdV), parainfluenza virus (PIV), influenza B or A virus, respectively. Detection of influenza A viral gene copies was most frequent even when there were no known infected patients in the room (72%). Influenza B, AdV and RSV were detected in low to moderate frequencies, whether there were infected patients in close proximity (13-50%) or not (12-25%). PIV was rarely detected even when air samplers were placed in close proximity to infected patients (8%). About 103–105 copies/m3 were detected for all detected respiratory viruses. Conclusions Healthcare workers and visitors likely have substantial exposure to various respiratory viruses including influenza A/B viruses, RSV and AdV in pediatric patient rooms, even in the absence of infected individuals in close proximity, suggesting the potential value of improving indoor ventilation or air disinfection in hospitals. ### Competing Interest Statement BJC has received honoraria from AstraZeneca, Fosun Pharma, GlaxoSmithKline, Moderna, Pfizer, Roche and Sanofi Pasteur. The authors report no other potential conflicts of interest. ### Funding Statement This work was supported in part by the Theme-based Research Scheme from the Research Grants Council of the Hong Kong Special Administrative Region, China [Project No. T11-712/19-N], the Guangzhou Medical University High-level University Clinical Research and Cultivation Program [Guangzhou Medical University released [2017] No. 160]; the Guangzhou Medical University High- level University Innovation Team Training Program [Guangzhou Medical University released [2017] No. 159]; and the Science Research Project of the Guangdong Province, China [Grant No. 2016A050503047]. ### 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 Institutional Review Board of the University of Hong Kong, and the First Affiliated Hospital of Guangzhou Medical University approved this study. All patients and parents or legal guardians provided verbal informed consent. Written consent was deemed unnecessary, given that the study involved environmental air sampling and information on patients' diagnoses was collected anonymously with no personal identifying information. 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