High air flow-rate electrostatic sampler for the rapid monitoring of airborne coronavirus and influenza viruses

Capturing virus aerosols in a small volume of liquid is essential when monitoring airborne viruses. As such, aerosol-to-hydrosol enrichment is required to produce a detectable viral sample for real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. To meet this requirement, the efficient and nondestructive collection of airborne virus particles is needed, while the incoming air flow rate should be sufficiently high to quickly collect a large number of virus particles. To achieve this, we introduced a high air flowrate electrostatic sampler (HAFES) that collected virus aerosols (human coronavirus 229E, influenza A virus subtypes H1N1 and H3N2, and bacteriophage MS2) in a continuously flowing liquid. Viral collection efficiency was evaluated using aerosol particle counts, while viral recovery rates were assessed using real-time qRT-PCR and plaque assays. An air sampling period of 20 min was sufficient to produce a sample suitable for use in realtime qRT-PCR in a viral epidemic scenario.

Automated summary

Efficient and nondestructive collection of airborne virus particles is essential for monitoring airborne viruses, with a high air flow rate required for quick sample collection. The introduction of a high air flowrate electrostatic sampler allows for continuous collection of virus aerosols in liquid, making it suitable for real-time qRT-PCR detection. A 20-minute air sampling period is sufficient for producing a sample suitable for use in a viral epidemic scenario.