Epidemiology Midterm, Spring ‘01

1 Page 1 of C:\DATA\HS161\ midterm , Spring 01 Sections covered on this exam: Preface, , , , , , , , and the Foodborne OutbreakFor the multiple choice questions, please use the Scranton (provided) to record your answers and select the bestresponse in each Public health is the study of the distribution anddeterminants of health and disease ** refers to disability and ** a disease simultaneously affects persons ofseveral countries or continents and effects themin numbers in clear excess of normalcy, thedisease is said to ** second leading cause of death in the US (malignant neoplasms) ** Snow s most important work ** was the best explanation for the lack ofcholera cases in the brewery near Broad Street?

2 Conferred immunity to killed the cholera Brewery workers had a Brewery workers hardly drank water ** major causes of mortality during the priorcentury were mostly acute and ** gap in life expectancy between whites no longer still evident and has still evident but has narrowed ** disease definable physiological or psychologicaldysfunction ** the patient state of dysfunction of the social role ofthe of the word Epidemiology is based on the sameroot as the word ** beginning of the subclinical period ofdisease is marked to the agent ** pathological changes of of prevention is intended to reduce theduration and severity of ** clinical stage of disease begins to the patient s first symptoms ** time of diagnosisPage 2 of C.

3 \DATA\HS161\ period between exposure and first symptomsis of stage of disease ** of clinical of stage of prevention is intended to reducecomplications and prevention ** natural history of disease refers progress of a disease in an individualover time ** period between exposure and period from first symptoms to recovery,disability, or broad scope of manifestations of adisease in different disease that occurs rarely and withoutregularity is said to ** particular infectious disease can display abroad scope of manifestations and is known as of infection ** level of of and direct causes of disease may form acomplex network of events that determines thelevel of disease in a community.

4 The complexinter-relation of events is called cause of web ** epidemiologic triad includes all of thefollowing factors ** of the following is a chemical cause ofdisease? excesses ** in the ability of a biologic agent toenter a host is ** of the following is a component of innateimmunity? phagocytic cells ** lower plants that lack chlorophyll are: and yeasts ** infectious agents that containtheir own genetic material but are incapable ofmultiplying outside of the host are: ** of the following can act as reservoirs? of the above **Page 3 of C:\DATA\HS161\ of the following can act as a portal? ** or false? Modified live vaccines representnon-virulent strains of the agents that arecapable of causing ** of the following is an active form ofimmunization?

5 ** that harbor a specific infectious agentwhile manifesting no discernable signs orsymptoms are ** with animal reservoirs ** convalescent carrier person who transmits the agent prior to theonset of animal infected person who has recovered fromdisease but still harbors and transmits theagent ** of the animal (usually an insect) that serves totransmit an agent is called ** disease with a urogenital portal is transmitted disease ** disease that is spread from human to human orfrom humans to animal in vehicle transfer ** nuclei water borne transmission of cholera via theBroad Street pump is an example vehicle spread ** nuclei proteins produced by B cells thatneutralize invading pathogens ** cell regulates the immune response?

6 Lymphocytes ** (natural killer) immunity is resistance that isdeveloped by the host as a result of a previousexposure to a natural or artificial pathogen orforeign ** of the following is a chemical barrier killer acidity ** intact skin often provides an effectivephysical barrier to ** disease outbreak investigationsinclude both an epidemiologic and ** 4 of C:\DATA\HS161\ ANSWER: Please respond directly on the Epidemiology . [3 pts]Study of / health or disease / in the four stages in the natural history of a disease [4 pts] resolution, disability, or plain terms, explain the meaning of the iceberg phenomenon. [2 pts]There s often a broad spectrum of disease manifestations / much of which can be inapparent, undiagnosed, orunreported.

7 Of the first steps in investigating an outbreak is to confirm the diagnosis of cases. Why is this important? [1pt]Purported outbreaks may actually represent sporadic occurrences of unrelated diseases (or even a psychologicalevent related to hysteria. did John Snow remove the handle from the Broad Street Pump? [1 pt]To prevent further occurrences of is a reservoir? [3 pts]Normal habitat or environment / in which the agent live and 5 of C:\DATA\HS161\ from a food borne outbreak are shown below. Use these data to complete the exam. Show workIDILLB loody diarrheaIncubation (hrs)Chicken SaladIce percentage of cases experienced bloody diarrhea?4 /4 = 100% is the median incubation period of this disease?)

8 2 the attack rate in those who ate chicken /4 = . the attack rate for those who did not eat chicken salad. (Show all work)3 / 6 = . the relative risk of illness associated with chicken / .5 = the attack rate in those who ate ice / 6 = . the attack rate in those who did not eat ice / 4 = . the relative risk of illness associated with ice / .25 = food is the more likely source of contagion? The chicken salad or the ice cream? Ice cream