AIM: We initially aimed to study the effects of face masks worn by recently infected individuals on the airborne spread of SARS-CoV-2, but findings motivated us to proceed with comparing the presence of SARS-CoV-2 in air samples near infected individuals at home with those near infected ICU patients. METHODS: We developed a high-volume air sampler method that used a household vacuum cleaner with surgical face masks serving as sample filters. SARS-CoV-2 RNA was harvested from these filters and analysed by polymerase chain reaction. Fog experiments were performed to visualize the airflow around the air sampler. We acquired air samples in close proximity of infected individuals, with or without wearing facemasks, in their homes. We also obtained environmental air samples remote from these infected individuals and samples near patients in the ICU undergoing potential aerosol-generating medical procedures. FINDINGS: Wearing a face mask resulted in a delayed and reduced flow of the fog into the air sampler. Face masks worn by infected individuals were found to contain SARS-CoV-2 RNA in 71% of cases. SARS-CoV-2 was detected in air samples regardless of mask experiments. The proportion of positive air samples was higher in the homes (29/41; 70.7%) than in the ICU (4/17; 23.5%) (p<0.01). CONCLUSION: SARS-CoV-2 RNA could be detected in air samples by using a vacuum cleaner based air sampler method. Air samples in the home environment of recently infected individuals contained nearly three times more often SARS-CoV-2 RNA in comparison to those obtained in ICU rooms during potential aerosol-generating medical procedures.
Airborne SARS-CoV-2 in home- and hospital environment investigated with a high-powered air sampler