CHAPTER 21 



The Rickettsiae 



HISTORICAL INTRODUCTION TO THE ORGANISMS 



CHARACTERISTICS OF RICKETTSIAE 



Morphology 

 Cultural requirements 



CLASSIFICATION 



RICKETTSIAL DISEASES AND THEIR VECTORS 



Rocky Mountain spotted fever 

 Boutonneuse fever 

 Typhus fever 

 Tsutsugamushi disease 

 Human rickettsialpox 

 "Q" fever 

 Heartwater disease 

 Trench fever 



LABORATORY DIAGNOSTIC TECHNIC 



METHODS FOR CONTROLLING RICKETTSIAL DISEASES 



HISTORICAL INTRODUCTION 



It was in 1909 that Howard T. Ricketts found small, spherical 

 and coccoid bacteria-like organisms in wood ticks. These microbes 

 are called rickettsiae in honor of their discoverer. Rickettsiae re- 

 semble bacteria in that they may be observed under the oil immer- 

 sion objective of an ordinary compound microscope, but they are 

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