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Statistical inferences about injury and persistence of environmentally stressed bacteria

Published online by Cambridge University Press:  15 May 2009

Martin A. Hamilton  and
Gary K. Bissonnette
Martin A. Hamilton
Affiliation:
Department of Mathematics
Gary K. Bissonnette
Affiliation:
Department of Microbiology, Montana State University, Bozeman, Montana, U.S.A.
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Summary

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A standard technique for ascertaining the survival characteristics of bacteria after being environmentally stressed is to incubate the bacteria on both selective and non-selective media and count the colonies produced. Based on these colony counts, indexes of injury and persistence of the bacteria are calculated. To compare the stress of two different environments, a persistence ratio is calculated. In this paper, methods of statistical inference concerning these indexes and ratios are presented. These statistical methods use well-known procedures for analysis of binomial data and 2 × 2 table data, and are appropriate when the colony counts follow a Poisson distribution.

Type
Research Article
Information
Journal of Hygiene , Volume 74 , Issue 2 , April 1975 , pp. 149 - 155
Copyright
Copyright © Cambridge University Press 1975

References

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