To What Extent Can Viable Bacteria in Atmospheric Aerosols be Dangerous for Humans?

Abstract

Multi-year monitoring of atmospheric bioaerosol in Southwestern Siberia revealed the presence of a large number of various culturable microorganisms. It is known that viable microorganisms can cause directly or provoke different human diseases. It's very difficult to evaluate the danger represented by each microorganism to man directly. Therefore, a relatively simple method is required for evaluation of potential danger represented to man by the whole assembly of culturable microorganisms in an atmospheric aerosol sample. For bacteria, the method can be based on a number of individual characteristics of each microorganism determined in the course of biochemical and other test required for identification of the detected bacterium, and a number of other tests. It is proposed to classify the measured individual characteristics of bacteria under four groups of indices responsible for: (i) potential pathogenicity for man; (ii) the numbers of bacteria in the sample; (iii) resistance to unfavorable environmental factors; (iv) drug resistance of bacteria. Each of four groups of indices is numerically evaluated by a certain integral index, which quantitatively reflects the contribution of experimentally determined characteristics of bacteria. Expert evaluation of the contribution of each characteristic of microorganisms to the corresponding group of indices is performed. The generalized index of potential danger of culturable bacteria in atmospheric aerosols for human health is presented as the product of four integral indices summarizing the normalized individual integral indices for all bacteria detected in the sample. The work presents the results of measuring the variations of all the above indices for atmospheric air samples collected during one year.

Characterization of Airborne Bacteria at an Underground Subway Station

“…To our knowledge, antibiotic resistance profiling of the airborne bacterial community in a subway station has not previously been addressed, but several studies have addressed antibiotic resistance of airborne bacteria in other specific environments (14,17,25,30,58), such as cattle, swine, or poultry farms (1,26,57). The results obtained in the present study show that most dominant bacterial genera have a very high frequency of resistance to NAL, except for Bacillus and Paenibacillus spp., which had 14 and 0% frequencies of resistance, respectively.…”

Topical Issue: Bioaerosol Research

“…The third paper of this category addressed the viability of bioaerosols in the atmosphere and questioned the extent of the health risk posed by the viable bacteria present in atmospheric aerosols. This collaborative investigation that involved a team of Russian researchers (Safatov, Andreeva, Belan, Buryak, Emel'yanova, Panchenko, Pechurkina, Puchkova, Repin, Saranina, and Sergeev of the State Research Center of Virology and Biotechnology "Vector", Novosibirsk Region, Russian Federation) and Ruprecht Jaenicke of Johannes Gutenberg -Universität Mainz in Germany, presented a novel approach for evaluating the pathogenicity of airborne bacteria with respect to its effect on regional population (South-West Siberia) [7]. While it is debatable if the proposed method is feasible for a routine monitoring of atmospheric aerosols or risk assessment, it was successfully used in this study.…”

How Has the Hazard to Humans of Microorganisms Found in Atmospheric Aerosol in the South of Western Siberia Changed over 10 Years?

“…We have previously proposed such an approach for determining the hazard of bacteria and yeasts found in atmospheric bioaerosols for humans and demonstrated its capabilities using the available experimental data as an example [28]. In the framework of the developed approach, a dimensionless integral index of the hazard to humans of microorganisms isolated from atmospheric bioaerosols was constructed, which is the product of four lower-level dimensionless integral indices characterizing the complex properties of the microorganism.…”

“…One of them is an integral index of the concentration of culturable bacteria in an aerosol sample. Other components of the integral index of the hazard of microorganisms to humans are [28]:…”

“…Obviously, the more culturable microorganisms (identical or different) are in the air, the more dangerous they are to humans. The value normalized to the maximum number of culturable microorganisms in all samples studied (or in one sample; in this case, of course, this index is equal to 1) represents the first index [28]. The second index assesses the hazard (pathogenicity or conditional pathogenicity) of microorganisms to humans.…”