Deck 19: Epidemiology

Question 1

Large respiratory droplets typically travel no farther from point of release than

A) 3 meters.
B) 5 meters.
C) 1 meter.
D) 20 meters.
E) 12 inches.

Answer 1

C

Question 2

Which of the following is considered a zoonotic disease?

A) Measles
B) Typhoid
C) Common cold
D) Influenza
E) Plague

Answer 2

E

Question 3

Diseases constantly present in a population are called

A) epidemic.
B) chronic.
C) latent.
D) endemic.
E) prodromic.

Answer 3

D

Question 4

Inanimate objects capable of transferring infectious disease agents are

A) vectors.
B) fomites.
C) vehicles.
D) reservoirs.
E) arthropods.

Question 5

An epidemic that spreads worldwide is called a(n)

A) epidemical.
B) endemic.
C) pandemic.
D) syndemic.
E) plague.

Question 6

A dramatic increase in the incidence of a specific disease in a given population is referred to as a(n)

A) pandemic.
B) endemic.
C) epidemic.
D) mortality.
E) outburst.

Question 7

Diseases that can be transmitted from one person to another are termed

A) symptomatic.
B) clinical.
C) acute.
D) latent.
E) communicable.

Question 8

The single most important measure to prevent the spread of disease is

A) hand washing.
B) canning.
C) pasteurization.
D) home cooking.
E) antibiotics.

Question 9

The number of people in a defined population who die during a given period is called the

A) mortality rate.
B) morbidity rate.
C) attack rate.
D) incidence rate.
E) case rate.

Question 10

Women died after childbirth of 

A) S. aureus intoxication.
B) toxic shock syndrome.
C) Klein's disease.
D) puerperal fever.
E) shock.

Question 11

Important sources of contamination in crowded locations are

A) droplets of blood.
B) droplets of saliva or mucus.
C) restrooms.
D) kitchen surfaces.
E) All of the answer choices are correct.

Question 12

Diseases that primarily exist in animals, but may be transmitted to humans are called

A) parasitic.
B) zoonotic.
C) symbiotic.
D) epidemic.
E) commensal.

Question 13

Gonorrhea is a disease that may be

A) zoonotic.
B) pandemic.
C) syndemic.
D) asymptomatic.
E) All of the answer choices are correct.

Question 14

The doctor responsible for introducing the idea of hand washing before attending patients was

A) Klein.
B) Semmelweis.
C) Koch.
D) Pasteur.
E) Galen.

Question 15

A cluster of cases in a specific population occurring in a brief period of time is called a(n)

A) outbreak.
B) endemic.
C) pandemic.
D) attack break.
E) mortality.

Question 16

The reservoir of infection for botulism and tetanus is

A) humans.
B) soil.
C) water.
D) animals.
E) soil AND water.

Question 17

Apparently healthy people who may transmit a pathogen they harbor are called

A) vectors.
B) carriers.
C) fomites.
D) vehicles.
E) arthropods.

Question 18

The natural habitat of a pathogen is referred to as its

A) home.
B) reservoir.
C) primary inhabitance.
D) infectious site.
E) place.

Question 19

Vertical transmission involves

A) droplet transmission.
B) fomites.
C) pregnant woman to fetus.
D) pasteurization.
E) insect to human.

Question 20

The number of cases of a specific disease per one hundred people exposed is called the

A) attack rate.
B) index rate.
C) mortality rate.
D) obesity rate.
E) attack index.

Question 21

Schistosomiasis has increased in areas where

A) snails have become a delicacy.
B) crayfish are eaten.
C) dams have been built.
D) swamps have been drained.
E) people fish for sport.

Question 22

If the number of people who become ill during an epidemic rises gradually, this is called a(n)

A) propagated epidemic.
B) promulgated epidemic.
C) common source epidemic.
D) index epidemic.
E) confluent epidemic.

Question 23

The publication of the CDC that reports new cases of reportable infectious diseases is titled

A) Morbidity and Mortality Weekly Report (MMWR).
B) State Health News Letter (SHNL).
C) Federal Report of Infectious Disease (FRID).
D) National Morbidity Weekly (NMW).
E) Monthly Death and Disease Report (MDDR).

Question 24

The amount of infecting agent received by susceptible individuals is called the 

A) exposure.
B) infectious number.
C) infectious dose.
D) infecting level.
E) infective exposure.

Question 25

So far, the only disease that has been globally eradicated is

A) polio.
B) smallpox.
C) measles.
D) diphtheria.

Question 26

The period of time between exposure to an agent and the onset of disease signs and symptoms is called the

A) prodromal phase.
B) decline phase.
C) incubation period.
D) lag phase.
E) carrier phase.

Question 27

Because of the natural evolution of microorganisms, it is necessary to use techniques that allow distinguishing them at the level of

A) species.
B) genus.
C) family.
D) strain.
E) domain.

Question 28

When an infectious disease cannot spread in a population because it lacks a significant number of susceptible hosts, the phenomenon is referred to as

A) protected population.
B) active immunity.
C) passive immunity.
D) herd immunity.
E) protective immunity.

Question 29

The World Health Organization (WHO) is part of the

A) Food and Drug Administration.
B) Department of Health and Human Services.
C) Department of Human Resources.
D) United Nations.
E) North Atlantic Treaty Organization.

Question 30

WHO has targeted for elimination of

A) polio.
B) dracunculiasis.
C) measles.
D) plague.
E) polio, dracunculiasis, AND measles.

Question 31

An experimental study in which neither the doctor nor the patient knows who is getting the actual treatment is called a ________ study.

A) single-sided
B) double-sided
C) double-blind
D) double-barrier
E) test-sided

Question 32

If the number of people who become ill during an epidemic rises and falls rapidly, this is called a(n)

A) propagated epidemic.
B) promulgated epidemic.
C) common source epidemic.
D) index epidemic.
E) contagious epidemic.

Question 33

Droplet nuclei typically travel no farther from point of release than

A) 3 meters.
B) 5 meters.
C) 1 meter.
D) 12 inches.
E) They are suspended indefinitely.

Question 34

The immunity of some black Africans to malaria is probably due to their

A) general health.
B) genetic background.
C) cultural practices.
D) age.
E) All of the answer choices are correct.

Question 35

Which of the following is not a vector?

A) Fomite
B) Human
C) Fly
D) Flea
E) Fomite AND human

Question 36

The type of epidemiological study that determines the characteristics of the persons involved and the time and place of the outbreak is called a(n)

A) descriptive study.
B) inspection study.
C) cohortive study.
D) retrospective study.
E) cohesive study.

Question 37

In order to prevent spread of microorganisms from the microbiology laboratory, the room air should be

A) under positive pressure AND filtered.
B) under negative pressure AND filtered.
C) under negative pressure, chilled, AND filtered.
D) under positive pressure, chilled, AND filtered.
E) under neutral pressure, chilled, AND filtered.

Question 38

A new serotype of Vibrio cholerae, V. cholerae 0139, has picked up the ability to produce

A) pili.
B) flagella.
C) a capsule.
D) a toxin.
E) endotoxin.

Question 39

Which of the following is not a mechanical vector?

A) Fomite
B) Human
C) Fly
D) Flea
E) Fomite AND human

Question 40

The first identified case in an outbreak is called the

A) starter case.
B) traceable case.
C) primary case.
D) index case.
E) initiator case.

Question 41

The member of the hospital staff who surveys the types and numbers of nosocomial infections is called the

A) head nurse.
B) infection control practitioner.
C) staff control.
D) attending physician.
E) external epidemiologist.

Question 42

Transmission-Based Precautions

A) is an online informative course all health workers must take on an annual basis.
B) are guidelines from WHO for dealing with emerging infectious diseases.
C) are instructions on the care of all patients given to nurses at their place of employment.
D) are guidelines to use with patients infected with a highly transmissible or epidemiologically important pathogen.
E) are guidelines given to patients before they enter the hospital to educate them on HAIs.

Question 43

The very young and the elderly are more susceptible to infectious disease.

Question 44

Which of the following is recommended by the Standard Precautions guidelines?

A) Glove use AND hand washing
B) Hand washing AND a face shield
C) A face shield AND antibiotics
D) Antibiotic use AND glove use
E) Glove use, hand washing, AND a face shield

Question 45

A placebo is a mock drug.

Question 46

All of the following are commonly associated with nosocomial disease EXCEPT

A) Enterococcus species.
B) Clostridium difficile.
C) Pseudomonas species.
D) Staphylococcus aureus.
E) Clostridium botulinum.

Question 47

A fly may serve as a mechanical vector.

Question 48

The guidelines designed for prevention of nosocomial disease during care of all patients is called

A) Standard Precautions.
B) Universal Disposables.
C) Disinfection Manifesto.
D) Asepsis Preference.
E) Hand Hygiene Precautions.

Question 49

Approximately what percentage of hospitalized patients may develop a nosocomial infection?

A) 0%
B) 5%
C) 15%
D) 20%
E) 70%

Question 50

Cross-sectional surveys are very useful in establishing cause of a disease.

Question 51

Prevention of patient-to-personnel transmission of disease depends on limiting contact with

A) patients.
B) personnel.
C) administrators.
D) physicians.
E) body fluids.

Question 52

An infection acquired during hospitalization is referred to as a(n) ________ infection.

A) antibiotic-induced
B) therapeutic
C) medication-stimulated
D) nosocomial
E) herd initiated

Question 53

Generally, the smaller the infective dose, the lower the chance of disease.

Question 54

A gradual rise in numbers during an epidemic indicates a common source epidemic.

Question 55

The threat of bioterrorism

A) is due largely to the ease of spread and severity of diseases AND has prompted WHO to prepare a readiness plan.
B) is due largely to the ease of spread and severity of diseases AND may include rarely seen infectious agents.
C) is exaggerated in light of the efficiency of our healthcare system AND has prompted WHO to prepare a readiness plan.
D) has prompted the CDC to prepare a readiness plan AND is due largely to the ease of spread and severity of diseases.
E) has prompted the WHO to prepare a readiness plan, may include rarely seen infectious agents, AND is due largely to the ease of spread and severity of diseases.

Question 56

The portal of entry typically has little effect on the course of a disease.

Question 57

Nosocomial infections are those acquired at a hospital.

Question 58

Which of the following contributes to nosocomial disease?

A) Susceptible population
B) Hospital environment
C) Other patients
D) Patient's own normal microbiota
E) All of the choices are correct.

Question 59

Diseases with long incubation periods are more likely to spread extensively.

Question 60

In a double-blind test the treating physician knows who is getting the actual treatment.

Question 61

Human population growth and expansion contribute to emergence of diseases.

Question 62

Why is it important to include a placebo in a scientific study to assess the effectiveness of a drug?

A) It's actually unethical to include a placebo and it is usually not done. If you have a drug that you know to be effective, it's unethical to withhold that treatment from an ill patient.
B) A placebo-treated group will determine if the changes observed in the drug-treated illness group are due to a psychological effect rather than a physiologic/pharmacologic one.
C) It isn't scientifically important to include a placebo. A placebo simply helps investigators satisfy the legal requirements of the Food and Drug Administration in their testing process.
D) A placebo-treated group will determine if the changes observed in the illness in this non-treated group are due to a physiologic/pharmacologic effect rather than a psychological one.
E) Both groups of people are actually given the drug and a placebo. This is a way to ensure patient compliance, without which the study would not yield any useable information.

Question 63

In this case, the reservoir of infection was likely the

A) chicken wings.
B) Susan.
C) flatware used at the picnic.
D) river in the park.
E) mosquitoes.

Question 64

All of the following is/are reservoirs of infection in a hospital setting EXCEPT

A) patient's normal microbiota.
B) other patients.
C) medical personnel.
D) visitors.
E) sterile surgical equipment.

Question 65

Select the sequence that indicates the steps that occur in the chain of infection.
1) Transmission.
2) Susceptible host.
3) Reservoir of infectious agent.
4) Portal of exit.
5) Portal of entry.

A) 3, 4, 1, 5, 2
B) 2, 3, 5, 4, 1
C) 1, 2, 3, 4, 5
D) 5, 3, 1, 2, 4
E) 3, 2, 1, 5, 4

Question 66

A picnic was attended by 1,000 people. Potato salad was served at the event. The next day, 140 people reported vomiting and diarrhea. What was the attack rate of this food-borne illness?

A) 1.4%
B) 14%
C) 140%
D) 10%
E) More information is needed.

Question 67

Which of the statements about transmission of pathogens is True?

A) Vertical transmission of a pathogen is from the environment to a person.
B) Horizontal transmission refers to spread of a pathogen from mother to fetus.
C) Sexual intercourse is an example of indirect contact.
D) Droplet transmission is a particularly important source of contamination in densely populated buildings such as schools.
E) Droplet nuclei are large drops of pathogen-containing fluid discharged by talking; they fall to the ground within a meter of the person.

Question 68

A fly that walks on feces and picks up E. coli O157:H7 then lands on food and transfers the microorganisms, is considered a

A) mechanical vector.
B) biological vector.
C) mechanical OR biological vector.
D) fomite.
E) cross-contaminator.

Question 69

In 1918-1919, an influenza virus infected about 500 million people worldwide, killing at least 50 million of them. This disease is best described as a(n) ________.

A) epidemic
B) pandemic
C) outbreak
D) sporadic outbreak
E) endemic disease.

Question 70

Explain the most likely reason why smallpox was successfully eradicated but rabies probably never will be.

A) Smallpox was only found in humans; rabies is found in numerous animal reservoirs. We cannot reasonably eliminate rabies in all of the animal reservoirs that exist.
B) It was far easier to vaccinate the world population against smallpox than against rabies, due to the lower number of injections required for the smallpox vaccine. It becomes a compliance issue.
C) Since there are very few cases of rabies each year, there is little financial incentive to push health organizations to eradicate the illness through worldwide vaccination.
D) The symptoms of smallpox are easier to identify than the symptoms of rabies, so some carriers of rabies are not accurately diagnosed. This can lead to asymptomatic carriers present within the population of susceptible individuals, spreading the virus.
E) Smallpox was eradicated because anyone who got the disease died from it, so at some point there was no reservoir for the virus. 

Question 71

Please select the False statement.

A) A common source epidemic occurs when all of the cases result from exposure to a single source of the infectious agent.
B) A case-control study occurs when all of the cases result from exposure to a single source of the infectious agent.
C) The natural habitat of a pathogen is called the reservoir of infection.
D) Herd immunity can never be overcome by a pathogen.
E) Emerging infectious diseases are those that are novel or have recently increased in incidence.

Question 72

The situation described in this case study is an example of a(n)

A) propagated epidemic, because one student became ill, followed by others over several days.
B) common-source epidemic, because several students became ill in the same time frame.
C) propagated epidemic, because several students became ill in the same time frame.
D) epidemic, because one student became ill and then spread the causative organism to many others.
E) cohort study, because there was a group of students all affected by the same pathogen.

Question 73

Explain how the incubation period can influence the spread of an infectious agent.

A) Incubation period does not affect the spread of an infectious agent. An infectious carrier will only spread the illness when they are showing acute symptoms. As such, the length of incubation period is not important for spreading the illness.
B) Depending on the microbe and the illness, an asymptomatic carrier in the incubation period might be shedding infectious microbes to his/her surroundings. In such a case, a longer incubation period would lead to a greater spread of the disease as the carrier comes into contact with more individuals while he/she is generally appearing to be healthy.
C) A very short incubation period will place a patient into the highly infectious active disease state sooner. Since people avoid contact with actively ill individuals, a very short incubation period will always lead to a decrease in the spread of an infectious disease.
D) A very long incubation period will place a patient into the highly infectious active disease state later. Since people generally avoid contact with actively ill individuals, a very long incubation period will always lead to a decrease in the spread of an infectious disease.
E) A short incubation period leads to an increase in the spread of an infectious agent. This is because diseases with a short incubation period are always far more severe than those with a long incubation period, so the infectious agent is spread more vigorously.

Question 74

Some populations more than others are likely to be affected by a given pathogen. Many population characteristics influence the occurrence of disease. Which of the following MOST likely explains why some students at the picnic did not get ill?

A) Herd immunity, that protects non-immune people from an infectious agent-the agent cannot spread in a population because most potential hosts are immune. Most students were probably immune to the foodborne pathogen.
B) Age, because the immune system starts to weaken after childhood, and consequently people are vulnerable to certain diseases when they reach adulthood. The younger students in the group remained healthy.
C) Behavioral practices, that significantly influence the rate and type of disease transmission; in this case the vegetarians and vegans remained healthy, suggesting that not eating meat protected them from the pathogen.
D) Gender, because females are always more likely than males to acquire gastrointestinal diseases due to differences in their gut normal microbiota populations. The students who got ill were all female.
E) None of these factors explain the outcome of the picnic.

Question 75

Which of the following pathogens/diseases would be the easiest to eradicate?

A) A pathogen that only infects humans and rarely causes signs and symptoms. 
B) A pathogen that only infects humans and causes obvious signs and symptoms.
C) A pathogen that causes disease in both animals and humans.
D) A pathogen that mostly infects animals but also sometimes causes disease in humans.
E) A disease that is asymptomatic and is carried by a large number of people in a population.

Question 76

Which pathogen is INCORRECTLY matched with a portal of exit?

A) Influenza virus-respiratory droplets.
B) Vibrio cholerae-feces.
C) Mycobacterium tuberculosis-droplets of saliva and mucus.
D) Neisseria gonorrhoeae-urethral and vaginal secretions.
E) E. coli-urine.

Question 77

Which of the following best defines an endemic disease?

A) It is a disease that has a much higher incidence than usual.
B) It is a disease that used to be common but is eradicated through vaccination programs.
C) It is a disease that is transmitted by an arthropod vector.
D) It is a disease that occurs naturally in animals but may spread to people.
E) It is a disease that is always present at some level in a population.

Question 78

The portal of entry of the pathogen causing illness in this case is the

A) skin.
B) large intestine.
C) nose.
D) mouth.
E) mucociliary escalator.

Question 79

Please identify the CORRECT statement regarding basic epidemiology concepts.

A) Contagious disease-an infectious disease that can not be transmitted from one host to another.
B) Attack rate-the number of susceptible people developing illness in a population exposed to an infectious agent.
C) Incidence-the total number of cases of a disease in a given population at any time or for a specific period.
D) Prevalence-the number of new cases of a disease in a population at risk during a specified time period.
E) Morbidity rate-the proportion of people diagnosed with a specific disease who die from that disease.

Question 80

Which of the following is NOT a political/societal reason for a decrease in rates of childhood immunizations?

A) Distrust of the healthcare body administering the vaccinations.
B) Distrust of the government funding the vaccination process.
C) A lack of a proper "cold chain" for stable transport of vaccines into tropical areas.
D) Distrust of the scientific community advocating for administration of vaccines.
E) Lack of awareness of the seriousness of diseases such as pertussis.