Sampling Respiratory Viruses in Exhaled Breath Using the Gesundheit-II (G-II)

Abstract

From COVID-19 to the emerging H5N1 “bird flu,” many diseases are airborne and can cause infection through inhalation. In this study, we are using the Gesundheit-II (G-II) machine, an exhaled breath (EB) sampler, to better understand the transmission of respiratory infections such as influenza, COVID-19, and RSV. By analyzing the viral shedding among infected individuals, we aim to determine how humans shed common respiratory viruses through their EB. We sampled from a cohort of 70-75 University of Maryland dormitory roommate pairs to provide a mid-turbinate (MT) swab and 30-minute EB samples using the Gesundheit-II bioaerosol sampler. Study participants were selected based on self-reported onset of symptoms. MT swabs and EB samples were screened for common respiratory viruses using Cepheid, and TaqMan Array Cards (TAC). Samples were cultured for influenza A virus using TCID₅₀ assay. Thus far, we have collected a total of seven MT swabs and seven G-II fine aerosol (≤5 µm) samples. Testing using TAC identified various pathogens in five of the MT swabs (influenza A virus, coronavirus OC43, S. aureus, and M. catarrhalis). Among the MT swabs cultured for influenza A virus, three yielded positive results. The influenza A Cepheid test results for MT swabs aligned with these TCID₅₀ findings. For fine aerosol samples, TAC results are pending and viable virus has not been detected. These data can provide insight into the airborne spread of various respiratory pathogens to better inform public health interventions needed to control outbreaks and mitigate future airborne virus pandemics by setting new standards for infection control.