Systematic review and meta-analysis of methodological approaches for characterising airborne SARS-CoV-2 RNA for environmental surveillance

Abstract SARS-CoV-2 has transformed our understanding of respiratory disease transmission, particularly through aerosols. This systematic review examines studies published up to October 2, 2024 and focused on filter-based sampling methods reviewing key sampling and molecular diagnostic parameters to characterise airborne SARS-CoV-2 RNA from filters. A total of 84 studies were reviewed, yielding 104 datasets from different environments, including 70 studies indoors, 8 outdoors and 6 sampling both indoors and outdoors. The findings suggest that sampling volume, type of filter and storage conditions after sampling affect the detection positivity rate of SARS-CoV-2 genetic material in aerosols sampled near infected individuals indoors. No sampling or analytical parameters were identified to be associated with detection or quantification. Further experiments are recommended to ascertain the optimal methodological parameters for characterising SARS-COV-2 RNA in aerosols for environmental surveillance, including early warning systems, non-intrusive environmental monitoring, managing COVID-19 outbreaks and characterising viral airborne transmission.