A project to evaluate technologies to prevent the spread of infectious bioaerosols is making progress. Led by Dr. Montse Torremorell at the University of Minnesota, the project is identifying existing and emerging technologies across different industries for their ability to contain bioaerosols in the face of swine disease outbreaks. Next steps will be to research feasibility and cost effectiveness of potential biocontainment technologies.
Currently the group is writing a report on the technologies to be considered for their implementation in agricultural settings. Technologies identified thus far include fibrous filtration, ionization, bipolar ionization, ultraviolet light type C, ultraviolet light type A, electrostatic precipitation, microwave, photo electrochemical oxidation, non-thermal plasmas, and air filters coated with antimicrobial materials.
Fibrous filtration, with 11 references in the review, is the most well-established and widely applied approach for biocontainment. Its method of action is the indiscriminate removal of particles from flowing airstreams. There is a balance between the particle size dependent removal efficiency for a filter, which should be as high as possible, and the pressure drop across the filter for a given flow rate, which is directly related to the energy costs of filter operation. Furthermore, filter loading increases pressure drop but also efficiency, and must be considered in filter application.
Ultraviolet light, with 16 references in the review, is an established route towards pathogen inactivation in aerosols, as nucleic acid molecules readily absorb photons near this wavelength (254 nm). UV-C (and potentially UV-A) sources can be incorporated in-ducts to directly inactivate pathogens in aerosols, in-conjunction with filters to inactivate collected pathogens, and in upper room bulbs to inactivate larger spaces. However, the latter typically cannot be operated continuously, as UV-C can be mutagenic or carcinogenic at high exposure levels.