Microbiology: An Evolving Science (Fourth Edition)
4th Edition
ISBN: 9780393615098
Author: John W. Foster, Joan L. Slonczewski
Publisher: W. W. Norton & Company
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Chapter 25.1, Problem 1TQ
Summary Introduction
To review:
Virulence of a microbe with LD50 (lethal dose 50%) with 5 Ă— 104 and another microbe of LD50 with 5 Ă— 107.
Introduction:
Virulence is a parameter by which the severity or degree of a disease is measured. The fatality rates of different microbes define the virulence of the pathogen. For example, Ebola and Marburg virus have fatality rates of 70% and hence, are highly virulent. Lethal dose 50% is used to measure the virulence of a microbe such as a virus or bacteria. It is the number of microbes needed for killing 50% of the experimental group of animal hosts.
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Microbes possess many different strategies to help them cause disease called virulence factors. Explain how two virulence factors work. For each virulence factor state the name of the mechanism, explain how it works and what advantage it gives the organism that helps it cause disease.
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Which of the following pathogens is the LEAST virulent?
1. Microbe B, ID50 = 1,000 cells
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Chapter 25 Solutions
Microbiology: An Evolving Science (Fourth Edition)
Ch. 25.1 - Prob. 1TQCh. 25.4 - Prob. 1TQCh. 25.4 - Prob. 2TQCh. 25.4 - Prob. 3TQCh. 25.4 - Prob. 4TQCh. 25.5 - Prob. 1TQCh. 25.6 - Prob. 1TQCh. 25.6 - Prob. 2TQCh. 25.6 - Prob. 3TQCh. 25.6 - Prob. 4TQ
Ch. 25.7 - Prob. 1TQCh. 25 - Prob. 1RQCh. 25 - Prob. 2RQCh. 25 - Prob. 3RQCh. 25 - Prob. 4RQCh. 25 - Prob. 5RQCh. 25 - Prob. 6RQCh. 25 - Prob. 7RQCh. 25 - Prob. 8RQCh. 25 - Prob. 9RQCh. 25 - Prob. 10RQCh. 25 - Prob. 11RQCh. 25 - Prob. 12RQCh. 25 - Prob. 13RQCh. 25 - Prob. 14RQCh. 25 - Prob. 15RQCh. 25 - Prob. 16RQCh. 25 - Prob. 17RQCh. 25 - Prob. 1TQCh. 25 - Prob. 2TQCh. 25 - Prob. 3TQCh. 25 - Prob. 4TQCh. 25 - Prob. 5TQ
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