Chapter 14 Mastering Microbiology
Which of the following examples would best fall under the science of epidemiology?
Determining what water source in the county is contaminated with Cryptosporidium oocytes.
Which of the following statements about biological transmission is FALSE?
Houseflies are an important vector.
Which of the following statements is FALSE?
The M in MRSA stands for mannitol.
Emergence of infectious diseases can be attributed to all of the following EXCEPT
The emergence of infectious diseases can be attributed to all of these.
Which statement best describes microbial antagonism?
The normal microbiota prevents a pathogen from establishing an infection by both taking up space and producing toxic substances.
Koch's postulates established criteria for proving that a specific organism causes a specific disease. Which of the following is NOT one of the criteria given by Koch's postulates?
The pathogen must be isolated from inoculated animals and must be different from the original organism.
Which of the following statements about healthcare-associated infections is FALSE?
The patient was infected before hospitalization.
Which of the following statements about the development of infectious diseases is correct?
The period of convalescence is the time during which the person regains health and fully recovers (back to the pre-disease state).
Which is an example of vehicle disease transmission?
The presence of Listeria on undercooked chicken served for dinner
Which mode of transmission best describes the spread of Cryptosporidium from reservoir to host?
Vehicle transmission via water.
The yeast Candida albicans does NOT normally cause disease because of
antagonistic bacteria.
In which of the following patterns of disease does the patient experience no signs or symptoms?
both incubation and convalescence
Which of the following diseases is NOT spread by droplet infection?
botulism
A researcher has performed a prospective study on a disease. To which specific kind of epidemiological study is this referring?
descriptive
The following choices list several types of diseases, along with factors that may contribute to their emergence. Which disease and associated factor do NOT match?
emergence of avian influenza A (H5N1); use of antibiotics
If a disease occurs at a fairly stable rate, it is said to be
endemic
Malaria is an infectious disease caused by infection with a protozoan. In certain tropical regions, malaria is constantly present. We would say that malaria is a(n) __________ disease in these regions.
endemic
A cold transmitted by a facial tissue is an example of
fomite
A disease in which the causative agent remains inactive for a time before producing symptoms is referred to as
latent
Focal infections initially start out as
local infections.
Which of the following pairs is mismatched?
malaria - foodborne transmission
A commensal bacterium
may also be an opportunistic pathogen.
The major significance of Robert Koch's work is that
microorganisms cause disease.
Pseudomonas bacteria colonized the bile duct of a patient following his liver transplant surgery. This is an example of a
nosocomial infection.
Which of the following definitions is INCORRECT?
secondary infection: a long-lasting illness
Koch observed Bacillus anthracis multiplying in the blood of cattle. What is the condition specifically called when bacteria are multiplying in the blood?
septicemia
Which of the following is classified as a latent disease?
shingles
A burn patient is one example of a compromised host.
true
A host is not considered diseased until an infection changes one's state of health.
true
Both normal and transient flora can become opportunistic pathogens.
true
For a particular disease at a specific time period, morbidity rates should always be equal or greater than mortality rates.
true
Testing the effectiveness of a new drug for anthrax would be best performed as an experimental study.
true
During his research on West Nile virus, Bill learned that this virus is placed within a functional grouping known as arboviruses. What is meant by the term arbovirus?
-An arbovirus is an arthropod-borne virus. -An arbovirus is maintained in nature through biological transmission.
Which of the following characteristics do commensalism, mutualism, and pathogenicity have in common?
-life cycle coordination between the host and symbiont -common physical requirements between the organisms
Which of the following is NOT a predisposing factor of disease?
-occupation -climate -genetic background -lifestyle
Which one of the following is a zoonosis?
-rabies -cat-scratch disease -Hantavirus pulmonary syndrome -tapeworm
Which of the following is a reservoir of infection?
-sick animal -sick person -hospital -healthy person
Which of the following can contribute to postoperative infections?
-using syringes more than one -antibiotic resistance -normal microbiota on the operating room staff -errors in aseptic technique
Which of the following would be considered a vector?
A fly carrying disease from fecal matter to food
Which of the following would be an example of disease transmission via indirect contact?
A student sneezes on her test booklet. The instructor grades it and catches her cold.
Which of the following would be considered a fomite?
An infected toy
How might a patient who is not being treated with an antibiotic still be exposed to an antibiotic?
Antibiotics can be used in aerosols, thereby entering the environment.
Which of the following statements is TRUE?
At least one member must benefit in a symbiotic relationship.
The CDC is located in
Atlanta, GA.
What type of nosocomial infection is likely to arise from intravenous catheterizations?
Bacteremia
Which of the following is considered a major category of transmission of disease?
Contact, vehicle, and vector transmission
During a six-month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever ≥ 39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints, fatigue, or feeling ill). A laboratory-confirmed case was defined as a positive result for antibodies against Coxiella burnetii. Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the previous three years. The etiologic agent of the disease in the situation is
Coxiella burnetii.
Which of the following situations would be likely to lead to an opportunistic infection?
E. coli is conveyed from its normal location in the colon to the urinary tract, where it is not normally found.
Which of the following is an example of the symbiotic relationship known as mutualism?
E. coli within the large intestine
Which of the following statements concerning pathology, infection, and disease is true?
Pathology refers to the study of structural and functional changes that occur in the body as a result of a disease.
How can health care workers reduce the occurrence of nosocomial infections?
Practice more stringent aseptic techniques
Which of the following represents an instance of commensalism?
Salmonella colonizes the gallbladder without any effect on the gallbladder.
Which of the following characteristics of a catheter should be considered, to help minimize the spread of nosocomial infections?
Single-use
Which of the following is NOT a verified exception in the use of Koch's postulates?
Some diseases are noncommunicable.
Why are invasive procedures likely to increase the risk of nosocomial infections?
These procedures allow microbes from the skin to enter the bloodstream of the patient.
How can surgeons help to limit nosocomial infections?
They should perform surgeries and invasive procedures only when absolutely necessary.
What is the role of epidemiology?
To learn how to treat and prevent various diseases.
Which of the following is a protozoan zoonosis that can be transmitted by direct contact?
Toxoplasmosis
Bloodstream infections are the least common forms of nosocomial infections.
True
Which of the following best describes why West Nile Virus is considered to be an emerging infectious disease?
West Nile virus outbreaks have increased in number and affected areas since 1937.
Which of the following is a fomite?
a hypodermic needle
During a six-month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever ≥ 39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints, fatigue, or feeling ill). A laboratory-confirmed case was defined as a positive result for antibodies against Coxiella burnetii. Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the previous three years. The situation is an example of
a zoonosis
A healthcare-associated infection (traditionally known as a nosocomial infection) is
acquired during the course of hospitalization.
Symptoms of disease differ from signs of disease in that symptoms
are changes felt by the patient.
Transient microbiota differ from normal microbiota in that transient microbiota
are present for a relatively short time.
Which of the following is NOT an example of microbial antagonism?
bacteria causing disease
When aerosols containing pathogens spread disease from a distance of less than one meter, it is considered
contact transmission.
Which of the following definitions is INCORRECT?
epidemic: a disease that is constantly present across the world
The science that deals with when diseases occur and how they are transmitted is called
epidemiology
A researcher only needs to select a cohort group when implementing an analytical epidemiological study.
false
Diseases that are referred to as emerging infectious diseases have only been discovered in the past fifty years.
false
MMWR is a publication by the CDC that reports specifically and only on emerging diseases.
false
Reservoirs of infections are always inanimate objects.
false
Which one of the following does NOT contribute to the incidence of healthcare-associated infections?
gram-negative cell walls
If a prodromal period exists for a certain disease, it should occur prior to
illness
One effect of washing regularly with antibacterial agents is the removal of normal microbiota. This can result in
increased susceptibility to disease.
A needlestick is an example of
indirect contact transmission by fomite.
Biological transmission differs from mechanical transmission in that biological transmission
involves reproduction of a pathogen in an arthropod vector prior to transmission.
Which of the following is NOT a communicable disease?
tetanus
Expected prevalence of a disease is
the expected occurrence of a disease based on past observations.
Cryptosporidiosis is caused by _________ .
the protozoan Cryptosporidium, spread via the fecal oral route
In which of the following diseases can gender be considered a viable predisposing factor?
urinary tract infections
The rise in herd immunity amongst a population can be directly attributed to
vaccinations
During a six-month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever ≥ 39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints, fatigue, or feeling ill). A laboratory-confirmed case was defined as a positive result for antibodies against Coxiella burnetii. Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the previous three years. The method of transmission of the disease in the situation was
vehicle
As a health care worker, you are keenly aware of how important it is to avoid harming patients. You worry about inadvertently transmitting an infectious disease to an already compromised individual. According to the CDC, what is the most important thing you can do to avoid this?
wash my hands before and after interacting with any patient
Epidemiology is defined as the study of
where and when a disease occurs, and how it is transmitted.
