User:Barbara (WVS)/sandbox/Passive air sampling (microorganisms)

Literature Review

Bergey, D. H., and John G. Holt. Bergey's manual of determinative bacteriology. Baltimore:

Williams & Wilkins, 1994. Print.

Cappuccino, James G., and Natalie Sherman. Microbiology : a laboratory manual. Redwood City, Calif: Benjamin/Cummings Pub. Co, 1992. Print.

This lab manual was valuable because it contains photos of yeasts growing on different media.

Napoli, Christian, Marcotrigiano, Bincenzo and Montagna, Maria Teresa. “Air sampling procedures to evaluate microbial contamination: a comparison between active and passive methods in operating theatres.”. BMC Public Health 2012 12:594.

This study compared high and low ‘traffic’ (occupancy) sampling in hospital operating rooms that were subject to continuous HEPA filtering and high air flows. Importantly, passive air sampling was correlated to active sampling indicating that the less complicated passive sampling will provide meaningful results.

Park, Uk Park, Yeom, Jeong-Kwan, Lee, Won Jae and Lee, Kyeong-Min. “Assessment of the Levels of Airborne Bacteria, Gram-Negative Bacteria and Fungi in Hospital Lobbies” International Journal of Environmental Research and Public Health. 2013, 10, 541-555.

This study was able to establish a correlation between ‘traffic’ (occupancy) and airborne levels of fungi, mold and gram-negative bacteria in hospital lobbies.

Srikanth, Padma, Sudharsanam, Suchitra and Steiberg, R. “Mold Rediation”. Indian Journal of Medical Microbiology. 2008, 26:4, 302-312

Methods for establishing a baseline or standard to compare airborne levels of microorganisms responsible for nosocomial infections are discussed. Modes of transmissions of airborne microbes are described-especially situations where immunocompromised individuals are being treated. The ‘traffic’ or population levels in an area is related to the levels of airborne microbes.

Sudharsanam, Suchithra, Sridanth, Padma, Sheela, Merline, and Steinberg, Ralph. “Study of the Indoor Air Quality in Hospitals in South Chennai, India – Microbial Profile.” Indoor and Built Environment. 2008; 17;5, pp435-441.

This particular study provided reproducible procedures that could be used as an international standard due to the simplicity and specific culture media used to assess air quality and microbial levels. If the procedures described in this paper were applied to passive air sampling done at CCAC, a true comparison could be performed between locations. This article was very informative.

Whyte, W and Niven, L. “Airborne Bacteria Sampling: The Effect of Dehydration and Sampling Time.” Journal of Prenteral Science and Technology. Pp 182-188 Volume 40, No. 5/September-October 1986.

Extended sampling time, with growth medium used actively or passively can affect the results of the sampling, but only by statistically insignificant amounts. A formula can be used to determine the numbers of microorganisms per cubic meter based upon the number of colonies on a plate per time period. vg(cm/s) = d2/312; vg=settling rate of bacteria due to gravity, c=concentration of bacteria in the air, a=area of the petri dish, d=diameter of the particle.

Yang, Chin S., and Patricia A. Heinsohn. Sampling and analysis of indoor microorganisms. Pacifica, Calif:     Wiley Interscience, 2007. Print. (not read)

Yang, Chin S., and Patricia A. Heinsohn. Sampling and analysis of indoor microorganisms. Pacifica, California. Wiley Interscience, 2007. Print

Husman, Tuula. “Health effects of indoor-air microorganisms.” Scand J Work Environ Health 1996; 22:5-13.

Microorganisms are identified that are consistently present in humid, moderate, and low humidity indoor environments. Symptoms related to airborne exposure to the microbes are described and include: upper and lower tract irritation, eye irritation, wheezing, headache, tiredness, hoarseness, respiratory infection, fatigue and nausea.

My preliminary review of the literature shows that yeasts were not specifically singled out of the Colony Forming Units (CFU) when the samples were assessed for the presence of fungi, molds and bacteria. This may have been because yeasts were included in fungi or mold counts. But this was not specifically addressed in the literature reviewed. This may be a potential weakness in the studies since yeasts can produce serious infections in weakened or immunocompromised individuals.