Soilborne and Arthropodborne

Chapter 12 Soilborne and Arthropodborne Bacterial Diseases

Chapter Summary and Essay Questions Chapter 12 continues the coverage of bacterial infections and diseases by focusing on two groups of pathogens, those transmitted in contaminated soil and those transmitted by infected arthropods. Among the significant diseases discussed in this chapter are three caused by endospore forming bacteria (anthrax, tetanus and gas gangrene), plague, and Lyme disease. In addition, diseases caused by Rickettsia and Ehrlichia are described, including typhus, Rocky Mountain spotted fever and human granulocytic anaplasmosis. On completing the chapter, you should be able to answer the following essay questions: a. List the various ways by which the anthrax bacillus can be transmitted in nature. b. Appraise the role of the anthrax as an agent for bioterrorism. c. Describe the sequence of events that takes place when tetanus bacilli grow in the dead tissue of an infected wound. d. Explain the difference between gangrene and gas gangrene. e. Write a short review of leptospirosis, including a description of the organism and some major symptoms of the disease. f. Name some occupations in which the individuals may be at risk for leptospirosis. g. Describe the characteristics of the plague organism, and identify the three forms of plague, specifying how each form is transmitted. hi. Locate the different areas of the body that can be affected in tularemia, and discuss the possible methods of transmission. i. Outline the relevant features of Lyme disease, beginning with the responsible organism and mode of transmission and proceeding to symptoms and treatment. j. Explain why relapsing fever is so named, and compare and contrast the two forms of the fever. k. Compare Rocky Mountain spotted fever and epidemic typhus with respect to causative agent, transmission, symptoms, treatment, and diagnosis. l. Discuss murine typhus, focusing on its transmission and symptoms as they compare with epidemic typhus. m. Describe the diseases caused by Ehrlichia and Anaplasma species