Bioaerosol sampling: sampling mechanisms, bioefficiency and field studies

Abstract

Investigations into the suspected airborne transmission of pathogens in healthcare environments have posed a challenge to researchers for more than a century. With each pathogen demonstrating a unique response to environmental conditions and the mechanical stresses it experiences, the choice of sampling device is not obvious. Our aim was to review bioaerosol sampling, sampling equipment, and methodology. A comprehensive literature search was performed, using electronic databases to retrieve English language papers on bioaerosol sampling. The review describes the mechanisms of popular bioaerosol sampling devices such as impingers, cyclones, impactors, and filters, explaining both their strengths and weaknesses, and the consequences for microbial bioefficiency. Numerous successful studies are described that point to best practice in bioaerosol sampling, from the use of small personal samplers to monitor workers' pathogen exposure through to large static samplers collecting airborne microbes in various healthcare settings. Of primary importance is the requirement that studies should commence by determining the bioefficiency of the chosen sampler and the pathogen under investigation within laboratory conditions. From such foundations, sampling for bioaerosol material in the complexity of the field holds greater certainty of successful capture of low-concentration airborne pathogens. From the laboratory to use in the field, this review enables the investigator to make informed decisions about the choice of bioaerosol sampler and its application.

Evaluation of bioaerosol samplers for the detection and quantification of influenza virus from artificial aerosols and influenza virus–infected ferrets

“…Assessing the burden of influenza virus in the air is technically and operationally challenging in real‐world settings such as healthcare institutions . Clinical and environmental studies have utilized a range of instruments to determine the risk of exposure to virus‐laden bioaerosols in health care and agriculture .…”

Seasonality in airborne bacterial, fungal, and (1→3)-β-D-glucan concentrations in two indoor laboratory animal rooms

“…This means the samples were not collected simultaneously. Also, the sampler cannot accurately monitor bioaerosol concentration due to the shear forces exerted on the bioaerosol particles within the jet, the impaction on the agar plates, and potential desiccation of the organisms 30. However, despite the drawback of reduced viability, impactors are frequently used for sampling airborne pathogens 31–33.…”

Biological Efficiency Testing According ISO 14698-1

“…The comparative tests were performed in an indoor room (7.0x 4.5x 4.0 m.) with doors and windows closed with the purpose to evaluate the microbial population in the room's atmosphere [4][5][6]. No people were present during the tests.…”