The study collected aerosol samples during peak MRT ridership hours over a period of a year using National Institute for Occupational Safety and Health (NIOSH) BC 251 2-stage aerosol samplers attached to personal backpacks carrying air pumps. Molecular analyses found that some of the collected samples tested positive for adenovirus, influenza A virus and respiratory syncytial virus (RSV) type A.
“It is a novel achievement to successfully collect molecular evidence of multiple aerosolised respiratory viruses from Singapore's MRT. Usually transit network studies focus on mapping surface-borne bacterial DNA and neglect to target aerosolised or respiratory-borne RNA viruses,” said Dr Gregory Gray, a Professor of the Duke-NUS Emerging Infectious Diseases (EID) Signature Research Programme and senior author of the study. “Our study demonstrates that bioaerosol sampling might have a practical application for the detection of respiratory pathogens in crowded public areas, such as transportation systems. This is important in terms of pandemic preparedness, as a bioaerosol sampling system does not require the timely acquisition of ethical approvals and informed consent needed to collect individual samples from human subjects.”
The researchers said that more research is needed before bioaerosol sampling can be deployed to safeguard public health but that they hope their findings will advance both the science and the technology to improve bioaerosol sampling techniques.