Exposition to airborne SARS-CoV-2 in household and hospitals settings as studied by a vacuum cleaner as a high-powered air sampler

de Man, P.; Ortiz Sanchez, M.; Bluyssen, P.; de Man, S.; Rentmeester, M.-J.; van der Vliet, M.; Wils, E.-J.; Ong, D.

Background. We aimed to study the presence of SARS-CoV-2 in air surrounding infected healthcare workers (HCW) in their homes versus infected patients who were undergoing potential aerosol-generating medical procedures (AGMP). We also studied the effect of different face masks worn bij infected persons on spread of SARS-CoV-2 into the air. Methods. We developed a high-volume air sampler method that uses a household vacuum cleaner with a surgical mask serving as a sample filter. SARS-CoV-2 RNA was harvested from these sample filters and analyzed on the presence of RNA by polymerase chain reaction. We acquired air samples in close aproximity of HCWs wearing different facemasks. Also, we obtained free air samples away from the infected HCWs and samples near intensive care unit (ICU) patients undergoing AGMP. Fog experiments were performed to visualize the airflow around our air sampler. Results. Aerosols were visibly suctioned into the vacuum cleaner when there was no face mask, whereas wearing a face mask resulted in a delayed and reduced flow of aerosols into the vacuum cleaner. The face masks that were worn by the HCWs were positive in 54-83% of cases. The proportion of positive air samples was higher in household settings of recently infected HCWs (29/41; 70.7%) compared to ICU settings (4/17; 23.5%) (p<0.01). Conclusion. This high-volume air sampler method was able to detect SARS-CoV-2 RNA in air samples. Air samples in the household environment of recently infected HCWs more frequently contained SARS-CoV-2 in comparison to those obtained in patient rooms during potential AGMP.