Test Bank For Microbiology: The Human Experience, 1st Edition

Chapter 02: Basic Concepts of Infectious Disease MULTIPLE CHOICE 1. What kind of relationship exists between microbiota and their human hosts? a. mutualistic c. endoparasitic b. pathogenic d. ectoparasitic ANS: A DIF: Easy REF: 2.1 OBJ: 2.1a Describe differences between microbiota and pathogens. MSC: Remembering 2. This image shows a person afflicted with athlete’s foot, which is caused by the fungus Trichophyton rubrum. T. rubrum is an example of a(n) a. endoparasite. c. mutualist. b. ectoparasite. d. fomite. ANS: B DIF: Moderate REF: 2.1 OBJ: 2.1a Describe differences between microbiota and pathogens. MSC: Applying 3. This graph shows the percent mortality in populations of lab animals exposed to increasing concentrations of two different pathogens (agent 1 and agent 2). What is the lethal dose 50% (LD50) of agent 2? a. 400 c. 800 b. 600 d. 1,000 ANS: B DIF: Moderate REF: 2.1 OBJ: 2.1c Differentiate between infectious dose and lethal dose. MSC: Understanding 4. Which of the following is NOT a fundamental attribute of a successful pathogen? a. host attachment c. nutrient acquisition b. immune avoidance d. wide host range ANS: D DIF: Moderate REF: 2.1 OBJ: 2.1d Discuss the fundamental attributes of a successful pathogen. MSC: Understanding 5. This image shows a rash associated with Rocky Mountain spotted fever. This rash is an example of a a. sign. c. sequelae. b. symptom. d. fomite. ANS: A DIF: Moderate REF: 2.2 OBJ: 2.2a Distinguish between the signs and symptoms of a disease. MSC: Understanding 6. Colonization occurs during which stage of an infectious disease? a. incubation phase c. decline phase b. invasive phase d. prodromal phase ANS: A DIF: Moderate REF: 2.2 OBJ: 2.2c Describe the five basic stages of an infectious disease. MSC: Applying 7. Which of the following is an example of a symptom? a. a rash c. jaundice (yellow tinge to the skin) b. swollen glands d. muscle aches ANS: D DIF: Moderate REF: 2.2 OBJ: 2.2a Distinguish between the signs and symptoms of a disease. MSC: Applying 8. A mosquito can transmit a viral pathogen into humans. The mosquito is an example of a(n) a. fomite. c. vector. b. symptom. d. endoparasite. ANS: C DIF: Easy REF: 2.3 OBJ: 2.3a Describe complex versus simple infection cycles. MSC: Remembering 9. An island nation normally has low background level of cholera. After an earthquake, sanitation is disrupted and cholera cases spike to high levels on the island but not in other areas of the world. The spike in cholera cases is an example of a(n) a. endemic disease. c. pandemic disease. b. epidemic disease. d. opportunistic infection. ANS: B DIF: Easy REF: 2.3 OBJ: 2.3b Differentiate endemic, epidemic, and pandemic disease. MSC: Understanding 10. Human immunodeficiency virus (HIV) spreads directly from person to person via intimate contact. HIV exhibits a. a simple infection cycle. b. a complex infection cycle. c. vehicle transmission. d. indirect transmission. ANS: A DIF: Easy REF: 2.3 OBJ: 2.3a Describe complex versus simple infection cycles. MSC: Understanding 11. Lily (who has lice) brings a comb to school for picture day. After Lily combs her hair, Leticia asks to borrow the comb. Leticia later is diagnosed with lice. In this example, the comb is a(n) a. carrier. c. incubator. b. fomite. d. portal. ANS: B DIF: Moderate REF: 2.3 OBJ: 2.3a Describe complex versus simple infection cycles. MSC: Understanding 12. Adhesins are proteins on the surface of microbes. Adhesins help most with which fundamental pathogen attribute? a. host attachment b. immune avoidance c. nutrient acquisition d. host mortality ANS: A DIF: Moderate REF: 2.1 OBJ: 2.1d Discuss the fundamental attributes of a successful pathogen. MSC: Understanding 13. The acme of an infectious disease, when the symptoms are most severe, occurs during which phase of the infection? a. incubation b. invasive c. decline d. prodromal ANS: B DIF: Moderate REF: 2.2 OBJ: 2.2c Describe the five basic stages of an infectious disease. MSC: Remembering 14. During which phase of an infectious disease do disease symptoms begin to subside? a. incubation c. decline b. prodromal d. convalescent ANS: C DIF: Easy REF: 2.2 OBJ: 2.2c Describe the five basic stages of an infectious disease. MSC: Remembering 15. What factor favors an infectious disease to become pandemic instead of epidemic? a. a localized animal reservoir c. a low infectious dose 50% b. rapid mortality d. a short incubation period ANS: C DIF: Difficult REF: 2.3 OBJ: 2.3b Differentiate endemic, epidemic, and pandemic disease. MSC: Evaluating 16. Walter defecates in the company restroom, does not wash his hands thoroughly, and then uses the office coffee pot, transferring bacteria onto the handle of the pot. Marcia pours some coffee and then goes to her desk to eat a muffin, ingesting some of the bacteria she picked up from the coffee pot. What is the route of transmission of this infection? a. fecal-oral c. urogenital b. respiratory d. parenteral ANS: A DIF: Easy REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Understanding 17. A mosquito can transmit a viral pathogen into humans. What is the mode of transmission of the virus in this instance? a. oral b. respiratory c. urogenital d. parenteral ANS: D DIF: Easy REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Remembering 18. This image shows a man sneezing, leading to an aerosol of pathogens. What is the most likely mode of transmission of these pathogens to another person? a. fecal-oral c. urogenital b. respiratory d. parenteral ANS: B DIF: Easy REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Understanding 19. Which of the following might be an effective means of limiting a disease spread via a urogenital route? a. using fresh needles, that is, not sharing needles b. wearing condoms during sexual activity c. wearing a mask that covers the nose and mouth d. washing hands before eating ANS: B DIF: Moderate REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Applying 20. Which of the following might be an effective means of limiting a disease spread via a parenteral route? a. not sharing needles b. wearing condoms during sexual activity c. wearing a mask that covers the nose and mouth d. cooking foods thoroughly ANS: A DIF: Moderate REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Applying 21. Which of the following might be an effective means of limiting a disease spread via an oral route? a. not sharing needles b. wearing condoms during sexual activity c. checking for and removing ticks after outdoor activity d. washing hands before eating ANS: D DIF: Easy REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Applying 22. The most dangerous potential bioterrorism agents have what portal of entry into the human body? a. respiratory b. urogenital c. parenteral d. fecal ANS: A DIF: Easy REF: 2.4 OBJ: 2.4b Discuss concepts of biosafety and biocontainment. MSC: Applying 23. This image shows a researcher working in a positive-pressure suit. Such attire is required to work with biological agents in which risk level? a. risk group I c. risk group III b. risk group II d. risk group IV ANS: D DIF: Easy REF: 2.4 OBJ: 2.4b Discuss concepts of biosafety and biocontainment. MSC: Remembering 24. Giardia lamblia, a cause of diarrhea and other gastrointestinal symptoms, is acquired from contaminated drinking water. It can be treated with several different antimicrobial drugs. Into what risk level does G. lamblia fall? a. risk group I c. risk group III b. risk group II d. risk group IV ANS: B DIF: Moderate REF: 2.4 OBJ: 2.4b Discuss concepts of biosafety and biocontainment. MSC: Evaluating 25. What factor is most responsible for both the very young and the very old being most susceptible to infectious diseases? a. the host genotype b. different portals of entry for pathogens c. the host immune system d. the inability of these populations to communicate symptoms to health care providers ANS: C DIF: Moderate REF: 2.5 OBJ: 2.5b Explain how host behavior can impact susceptibility to disease. MSC: Remembering 26. Which of the following can weaken the host immune response? a. too little sleep c. proper nutrition b. moderate exercise d. avoiding alcohol and drugs ANS: A DIF: Easy REF: 2.5 OBJ: 2.5a Define the biological features of human hosts that influence the course of an infection. MSC: Remembering 27. Which of the following host factors can prevent disease by limiting exposure? a. too little sleep c. working in the health care field b. moderate exercise d. proper hygiene ANS: D DIF: Easy REF: 2.5 OBJ: 2.5b Explain how host behavior can impact susceptibility to disease. MSC: Applying 28. During which phase of an infectious disease are immunopathologies most likely to first appear? a. incubation b. invasive c. decline d. convalescent ANS: B DIF: Moderate REF: 2.2 OBJ: 2.2b Explain the role of immunopathogenesis in infectious disease. MSC: Applying 29. Known diseases that rapidly increase in incidence and/or geographic range are known as a. emerging. c. zoonotic. b. reemerging. d. etiologic agents. ANS: B DIF: Easy REF: 2.6 OBJ: 2.6a Explain how efforts to expand civilization impact emerging infectious diseases. MSC: Remembering 30. Which number in the graph shown corresponds to the decline phase of an infectious disease? a. 2 c. 4 b. 3 d. 5 ANS: C DIF: Moderate REF: 2.2 OBJ: 2.2c Describe the five basic stages of an infectious disease. MSC: Analyzing 31. Infectious dose is measured by determining how many microbes are required to cause a. disease symptoms in half of an experimental group of hosts. b. death in half of an experimental group of hosts. c. disease symptoms in all of an experimental group of hosts. d. death in all of an experimental group of hosts. ANS: A DIF: Easy REF: 2.1 OBJ: 2.1c Differentiate between infectious dose and lethal dose. MSC: Remembering 32. The ability of a microbe to cause disease is known as a. emergence. c. pathogenicity. b. invasiveness. d. virulence. ANS: C DIF: Easy REF: 2.1 OBJ: 2.1c Differentiate between infectious dose and lethal dose. MSC: Remembering 33. Which of the following is most likely true of pathogens with a broad host range? a. The pathogens are highly virulent in all hosts. b. The pathogens are unlikely to be zoonotic diseases. c. The pathogens are less likely than narrow host range pathogens to respond to antibiotics. d. The pathogens recognize receptors that are very similar among different hosts. ANS: D DIF: Difficult REF: 2.1 OBJ: 2.1d Discuss the fundamental attributes of a successful pathogen. MSC: Evaluating 34. Which of the following is NOT true of climate change? a. b. c. d. Climate change will not affect human disease patterns. Climate change can alter insect vector distribution. Climate change can foster emerging diseases. Climate change can foster reemerging diseases. ANS: A DIF: Easy REF: 2.6 OBJ: 2.6b Explain how climate change can alter infectious disease patterns. MSC: Remembering 35. A particular virus has a high infectious dose 50% and extremely low mortality, causing only mild symptoms. Which of the following is true of this virus? a. It has high infectivity and high virulence. b. It has high infectivity but low virulence. c. It has low infectivity and low virulence. d. It has low infectivity and high virulence. ANS: C DIF: Difficult REF: 2.1 OBJ: 2.1b Discuss the relationship between infection and disease and between virulence and pathogenicity. | 2.1c Differentiate between infectious dose and lethal dose. MSC: Analyzing 36. Francisella tularensis is a highly infectious bacterium that can be contracted via multiple routes including inhalation. It causes severe disease but is treatable. Into what risk level does F. tularensis fall? a. risk group I c. risk group III b. risk group II d. risk group IV ANS: C DIF: Moderate REF: 2.4 OBJ: 2.4b Discuss concepts of biosafety and biocontainment. MSC: Evaluating 37. The main reason that climate change can affect infectious disease patterns is by a. causing the evolution of new animal species that can serve as hosts to emerging pathogens. b. altering where organisms can live. c. increasing the virulence of pathogens. d. decreasing the virulence of pathogens. ANS: B DIF: Moderate REF: 2.6 OBJ: 2.6b Explain how climate change can alter infectious disease patterns. MSC: Analyzing 38. Which of the following is NOT a driver of emerging diseases? a. decreased human drug use c. microbial evolution b. climate change d. changing land use patterns ANS: A DIF: Moderate REF: 2.6 OBJ: 2.6a Explain how efforts to expand civilization impact emerging infectious diseases. MSC: Understanding 39. Transplacental transmission is an example of a. fecal-oral transmission. c. indirect transmission. b. vehicle transmission. d. direct transmission. ANS: D DIF: Moderate REF: 2.3 OBJ: 2.3a Describe complex versus simple infection cycles. MSC: Applying 40. What is the difference between an emerging and a reemerging disease? a. Emerging diseases are of viral origin, and reemerging diseases are bacterial. b. Emerging diseases are ones for which vaccines exist; reemerging diseases lack vaccines. c. Emerging diseases are new to humans; reemerging are known but are rapidly increasing in incidence and/or geographic range. d. Emerging diseases evolve within humans, but reemerging diseases are of zoonotic origin. ANS: C DIF: Easy REF: 2.6 OBJ: 2.6a Explain how efforts to expand civilization impact emerging infectious diseases. MSC: Remembering 41. CASE HISTORY In 1884, Yong Ding was a 38-year-old male in Canton, located in southern China. Life was hard, but Yong Ding, a cook, still managed to support his family. As he walked to his restaurant each day, he barely noticed the small bands of rats scurrying through the streets. Disease was rampant that year; victims of the Shuyi (rat epidemic) were stacked like firewood in the streets, five bodies high in places, waiting to be taken to burial. Yong knew that the disease started as a swollen gland in the armpit and often had a black appearance (now called a bubo). He checked himself daily for these swellings and, seeing none, always felt relief. Then, one morning, he found one. Within days, Yong Ding began coughing blood as the agent (a mystery at the time) spread through his bloodstream to his lungs. Once that happened, Yong Ding knew death was not far behind. More than 60,000 died this way in what was to be the start of the Third Pandemic of bubonic plague. Yong Ding’s body was one of many lining the street that year. We now know that the cook Yong Ding was living through the Third Epidemic of bubonic plague. We also know that the rats that scurried randomly through the streets were infested with fleas, which carried the causative agent of the bubonic plague: Yersinia pestis. In this complex infection cycle, which organism was the vector? a. Yersinia pestis b. rats c. fleas d. humans ANS: C DIF: Easy REF: Case History 2.2 OBJ: 2.3c Explain animal reservoirs and incubators. MSC: Applying COMPLETION 1. The ability of a microbe to attach to a body surface is known as ________. ANS: colonization DIF: Moderate REF: 2.1 OBJ: 2.1a Describe differences between microbiota and pathogens. MSC: Remembering 2. This graph shows the percent mortality in populations of lab animals exposed to increasing concentrations of two different pathogens (agent 1 and agent 2). Agent ________ is more virulent. ANS: 1 one DIF: Moderate REF: 2.1 OBJ: 2.1b Discuss the relationship between infection and disease and between virulence and pathogenicity. MSC: Evaluating 3. A fever is often a host response to a pathogen. As such, fever is an example of ________. ANS: immunopathology DIF: Difficult REF: 2.2 OBJ: 2.2b Explain the role of immunopathogenesis in infectious disease. MSC: Understanding 4. The typical signs and symptoms of a disease first appear during the ________ phase of an infectious disease. ANS: invasive DIF: Moderate REF: 2.2 OBJ: 2.2c Describe the five basic stages of an infectious disease. MSC: Remembering 5. A disease that can spread to humans from nonhuman animals is known as a ________ disease. ANS: zoonotic DIF: Easy REF: 2.3 MSC: Remembering OBJ: 2.3c Explain animal reservoirs and incubators. 6. An infectious disease that rapidly increases in incidence throughout the world is known as a ________. ANS: pandemic DIF: Easy REF: 2.3 OBJ: 2.3b Differentiate endemic, epidemic, and pandemic disease. MSC: Remembering 7. In some parts of the world, human immunodeficiency virus is endemic. Endemic diseases require a reservoir to serve as a source of pathogen. ________ are the reservoir for HIV. ANS: Humans DIF: Moderate MSC: Applying REF: 2.3 OBJ: 2.3c Explain animal reservoirs and incubators. SHORT ANSWER 1. Describe the difference between an infection and a disease. ANS: An infection occurs any time a pathogen enters or starts to grow on a host. An infection does not necessarily lead to disease—a disruption of the normal structure or function of any body part, organ, or system that can be recognized by a characteristic set of symptoms and signs. DIF: Moderate REF: 2.1 OBJ: 2.1b Discuss the relationship between infection and disease and between virulence and pathogenicity. MSC: Understanding 2. Why is the lethal dose 50% easier to determine than the infectious dose 50%? ANS: The LD50 has a clear end point of death, so it is easy to measure. The ID50 is measured by determining how many microbes are required to cause disease symptoms in half of an experimental group of hosts. Disease symptoms may be hard to measure in nonverbal animals and may be more subjective. DIF: Difficult REF: 2.1 OBJ: 2.1c Differentiate between infectious dose and lethal dose. MSC: Evaluating 3. What distinguishes simple from complex infection cycles? ANS: In a simple infection cycle the pathogen passes directly from one individual to another. In a complex infection cycle the pathogen is not transmitted via direct contact but instead is transmitted indirectly through an intermediary such as a fomite or a vector. DIF: Moderate REF: 2.3 OBJ: 2.3a Describe complex versus simple infection cycles. MSC: Analyzing 4. What is the difference between a sign and a symptom? ANS: Signs (such as rashes) can be observed by others. Symptoms (body aches) cannot be directly observed by others but are felt by the patient. DIF: Easy REF: 2.2 OBJ: 2.2a Distinguish between the signs and symptoms of a disease. MSC: Remembering 5. Why do some public health departments widely spray insecticides in the spring and summer? ANS: Because mosquitoes and other insects often serve as pathogen vectors and reservoirs, limiting insect populations can decrease human disease incidence. DIF: Difficult MSC: Applying REF: 2.3 OBJ: 2.3c Explain animal reservoirs and incubators. 6. What is immunopathology? ANS: Immunopathology refers to disease signs and symptoms caused by the host immune system in response to the pathogen. Immunopathologies may include runny nose, fever, rash, and headache. DIF: Moderate REF: 2.2 OBJ: 2.2b Explain the role of immunopathogenesis in infectious disease. MSC: Understanding 7. Describe how bacterial adhesins affect the preferred entry portal of pathogens. ANS: To initiate a productive infection, bacteria must attach to host cells. Attachment is mediated by bacterial adhesins binding to host receptors. Different portals of entry contain different kinds of host cells with different receptors. The adhesins may only allow attachment to cells in certain portals. DIF: Difficult REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Analyzing 8. Describe how a pathogen could use an exit portal different from the portal it used to enter the host. ANS: Possible answers include the following: diarrhea-causing bacteria and viruses can enter via the oral route but leave via defecation; HIV can enter via the urogenital route and leave via the parental route in a needle (or vice versa—enter via a needle and exit via urogenital). DIF: Moderate REF: 2.4 OBJ: 2.4a Describe the various portals of entry and exit for microbial pathogens. MSC: Applying 9. What distinguishes risk level III from risk level IV organisms? ANS: While both risk level III and risk level IV pathogens can lead to lethal diseases, level IV pathogens tend to be more virulent and lack treatment options. DIF: Moderate REF: 2.4 OBJ: 2.4b Discuss concepts of biosafety and biocontainment. MSC: Remembering 10. List a few host factors that can influence the course of an infection by impacting immune status. ANS: Host age, nutritional status, and the presence of other diseases (e.g., HIV) can all affect host immune status. DIF: Easy REF: 2.5 OBJ: 2.5a Define the biological features of human hosts that influence the course of an infection. MSC: Remembering 11. CASE HISTORY Brandon, a 30-year-old stockbroker living in Chicago, visited his physician’s office. When the nurse asked Brandon why he was there, he blushed and said he wanted to talk only to the physician about his problem. Once the doctor entered the room, Brandon explained he had a small round lesion on his penis. When asked about his sexual partners, Brandon initially said he was dating only one woman, but when pressed, he admitted he had been intimate with two women over the past month and one man. Upon examination, the lesion appeared to cause no pain but exuded a clear fluid. The physician quickly sent a sample of the fluid to the clinical laboratory. There the sample was found to contain highly motile, corkscrew-shaped bacteria. The diagnosis was syphilis, caused by the bacterium Treponema pallidum. Left untreated, the disease could eventually cause horrible disfiguration and death. Confident that he knew the cause, the physician gave Brandon a shot of long-acting penicillin. What signs and/or symptoms of disease (distinguish between the two in your answer) did Brandon’s doctor note as a part of this diagnosis? ANS: Signs include lesion and fluid exudate. Symptoms include painlessness of lesion. DIF: Easy REF: Chapter 2 Introduction OBJ: 2.2a Distinguish between the signs and symptoms of a disease. MSC: Applying 12. CASE HISTORY In 2004, three people in Boston came down with a virulent form of pneumonia. An investigation by public health officials discovered that all three worked at the same laboratory studying Francisella tularensis, a bacterium that is highly infectious (although not usually spread by person-to-person contact). Under specific conditions, the organism can be aerosolized and inhaled and cause deadly pneumonia—making it a possible bioterrorism agent. Its handling is highly restricted by U.S. Homeland Security. Scientists studying this bacterium must use extreme precautionary measures to ensure that it cannot escape the laboratory. The investigation determined that the Boston researchers had indeed contracted tularemia. The scientists appear to have handled the organism in several instances without wearing or using proper protective gear—for example, examining agar plates containing the organism outside a biosafety containment hood. From the type of disease and the laboratory procedures performed, it seemed that the victims, who all fully recovered, inhaled the organism while working with it. When working with a Risk Group III level organism, the scientists should have known what types of precautions to take to decrease their risk of susceptibility. What are protective measures they should have used to decrease their risk of susceptibility? ANS: Protective measures should have included a biosafety containment hood and personal protective equipment. DIF: Moderate REF: Case History 2.3 OBJ: 2.4b Discuss concepts of biosafety and biocontainment. MSC: Applying