A. The majority of microorganisms are pathogenic.
B. Microorganisms that make up the normal microbiota of an individual never cause disease.
C. Pathology refers to the study of structural and functional changes that occur in the body as a result of a disease.
D. The term infection is synonymous with the term disease.
A. a tapeworm in the gastrointestinal tract of a human
B. E. coli within the large intestine
C. saprophytic Mycobacterium of the ear
D. Corynebacterium on the surface of the eye
This is not one of the criteria. According to Koch’s postulates, the pathogen isolated from the inoculated animals must be the same as the original organism.
A. The pathogen must be isolated from inoculated animals and must be different from the original organism.
B. The pathogen must be isolated from the diseased host and grown in pure culture.
C. The pathogen isolated from a pure culture must cause the disease in a healthy lab animal.
D. The same pathogen must be present in every case of the disease.
A. tuberculosis
B. infectious mononucleosis
C. shingles
D. influenza
A. direct contact transmission
B. vehicle transmission
C. droplet transmission
D. indirect contact transmission
A. vehicle transmission
B. vector transmission
C. contact transmission
D. There is not enough information to determine the mode of transmission.
A. direct contact transmission
B. vehicle transmission
C. vector transmission
D. indirect contact transmission
A. tapeworm
B. West Nile encephalitis
C. ringworm
D. Lyme disease
A. Mr. Smith sneezes on an airplane, and the person sitting beside him catches his cold.
B. A student sneezes on her test booklet. The instructor grades it and catches her cold.
C. A restaurant worker has diarrhea caused by Norovirus. He fails to wash his hands adequately before preparing the salad, and his customers get sick.
D. A tick that is infected with Lyme disease bites a hiker, and the hiker gets Lyme disease.
8%
40%
15%
20%
11%
A. Lower respiratory
B. Bacteremia
C. Urinary tract
D. Surgical
E. Cutaneous
A. Antibiotics can be used in aerosols, thereby entering the environment.
B. Visitors currently being treated with antibiotics can pass them on to the patient.
C. Health care workers being treated with antibiotics may pass the antibiotic on to the patient.
A. Invasive procedures require long term hospital stays, thereby increasing the number of visitors seen by the patient.
B. These procedures allow microbes from the skin to enter the bloodstream of the patient.
C. These procedures are carried out by health care workers, who carry resistant microbes.
D. Invasive procedures must use antibiotics.
A. Limit the number of visitors who can see the patient
B. Administer all medications orally instead of through injections
C. Practice more stringent aseptic techniques
D. Reduce the number of times they visit a patient
A. should be the primary concern of the healthcare worker.
B. is secondary to the health of the healthcare worker.
C. is secondary to the health of co-workers in healthcare settings.
A. They should perform surgeries and invasive procedures only when absolutely necessary.
B. They should prescribe as many antibiotics as possible.
C. They should only operate on healthy individuals.
D. They should prescribe immunosuppressive drugs to their patients.
A. they should leave the healthcare facility immediately.
B. they should immediately bring it to the attention of the healthcare worker.
C. they should immediately wash their hands.
A. Reusable
B. Washable
C. Single-use
D. Inexpensive
E. Long
A. Hand washing should be done frequently by patients.
B. Hand washing should be done frequently by healthcare workers.
C. Frequent and proper hand washing should be routinely done by patients and by healthcare workers, both prior to and after interaction.
D. Hand washing should be done before and after patient interaction.
A. where a disease occurs.
B. where and when a disease occurs, and how it is transmitted.
C. when a disease occurs.
D. how a disease is transmitted.
A. To learn which organisms cause disease.
B. To learn how to treat and prevent various diseases.
C. To learn what diseases can be caused by respiratory pathogens.
D. To learn which medicines are effective at killing pathogens.
A. the number of new cases of a disease over a period of time.
B. the total number of cases of a disease over a period of time.
C. the expected occurrence of a disease based on past observations.
D. the anticipated geographical spread of a disease based on past observances.
A. The disease has spread to North America from Europe.
B. The disease occurs at a lower rate than what would normally be expected in this region.
C. The disease occurs at a higher rate than what would normally be expected in this region.
D. Only a few cases are occurring in this region.
Four
Two
Six
Five
A. April of year four
B. March of year two
C. January of year four
D. September of year three
E. January of year three
A. endemic.
B. sporadic.
C. epidemic.
D. pandemic.
A. A fly
B. A tick
C. Contaminated water
D. An infected toy
A. Saliva that is transmitted between individuals during kissing
B. A fly carrying disease from fecal matter to food
C. Water droplets that come from a sneeze from an infected individual
D. Water containing bacteria from fecal matter
A. vector transmission.
B. contact transmission.
C. airborne transmission.
D. waterborne transmission.
A. Vehicle transmission
B. Contact, vehicle, and vector transmission
C. Vector transmission
D. Contact transmission
A. Touching a telephone with cold viruses on its surface
B. The transmission of MRSA from skin to skin contact
C. The bite of a mosquito containing malaria
D. The presence of Listeria on undercooked chicken served for dinner
A. Increased incidence of Lyme disease: increases in deer populations
B. increased incidence of malaria: global warming
C. spread of cholera to new regions: modern travel
D. emergence of avian influenza A (H5N1): use of antibiotics
A. Shave my head.
B. Wear a lab coat.
C. Wear shoe covers.
D. Wash my hands before interacting with any patient.
A. The period of decline is the time when the infected individual’s health rapidly deteriorates.
B. The prodromal period is characterized by very severe symptoms.
C. During the incubation period, the infected individual exhibits obvious signs of sickness.
D. The period of convalescence is the time during which the person regains health and fully recovers (back to the pre-disease state).
A. sporadic
B. epidemic
C. pandemic
D. endemic
A. body odor.
B. no bacterial growth because washing removes their food source.
C. increased susceptibility to disease.
D. fewer diseases.
E. normal microbiota returning immediately.
The etiologic agent of the disease in the situation is
A. wind.
B. sheep.
C. soil.
D. pneumonia.
E. Coxiella burnetii.
A. does not infect its host.
B. does not receive any benefit from its host.
C. is beneficial to its host.
D. may also be an opportunistic pathogen.
E. is beneficial to, and does not infect, its host.
A. At least one member must not benefit in a symbiotic relationship.
B. At least one member must benefit in a symbiotic relationship.
C. Symbiosis refers to different organisms living together and benefiting from each other.
D. A parasite is not in symbiosis with its host.
E. Members of a symbiotic relationship cannot live without each other.
A. are present for a relatively short time.
B. cause diseases.
C. are always acquired by direct contact.
D. are found in a certain location on the host.
E. never cause disease.
A. bacteria competing for nutrients
B. acid production by bacteria
C. bacteria causing disease
D. bacteriocin production
E. bacteria occupying host receptors
A. the transient microbiota
B. parasitic bacteria
C. other fungi
D. the normal microbiota
A. diseases can be transmitted from one animal to another.
B. microorganisms cause disease.
C. microorganisms can be cultured.
D. microorganisms are present in a diseased animal.
E. microorganisms are the result of disease.
A. focal infection
B. septicemia
C. local infection
D. systemic infection
E. bacteremia
A. Some human diseases have no other known animal host.
B. Some pathogens can cause several disease conditions.
C. Some diseases are not caused by microbes.
D. Some diseases are noncommunicable.
E. Some diseases have poorly defined etiologies.
A. endemic: a disease that is constantly present in a population
B. pandemic: a disease that affects a large number of people in the world in a short time
C. incidence: number of new cases of a disease
D. sporadic: a disease that affects a population occasionally
E. epidemic: a disease that is endemic across the world
A. local infections.
B. systemic infections.
C. septicemia.
D. bacteremia.
E. sepsis.
A. None of the answers is correct.
B. improved handwashing.
C. antibiotic-resistant microorganisms.
D. vaccinations.
E. increased use of antibiotics.
A. AIDS
B. typhoid fever
C. malaria
D. tetanus
E. tuberculosis
A. always occur as part of a syndrome.
B. are changes observed by the physician.
C. are specific for a particular disease.
D. are changes felt by the patient.
E. None of the answers is correct.
A. secondary infection: a long-lasting illness
B. chronic: a disease that develops slowly and lasts for months
C. acute: a short-lasting primary infection
D. primary infection: an initial illness
E. inapparent: infection characteristic of a carrier state
a
b
c
d
The answer cannot be determined based on the information provided.
A. February
B. The answer cannot be determined based on the information provided.
C. March
D. July
E. January
A. latent.
B. acute.
C. subclinical.
D. subacute.
E. zoonotic.
A. communicable disease.
B. epidemic level.
C. pandemic.
D. sporadic infection.
E. endemic level.
A. genetic background
B. None of the answers are correct; all of these are predisposing factors of disease.
C. lifestyle
D. occupation
E. climate
A. tetanus
B. anthrax
C. salmonellosis
D. urinary tract infections
E. pneumonia
A. decline
B. prodromal
C. convalescence
D. incubation
E. incubation and convalescence
A. convalescence.
B. decline.
C. illness.
D. incubation.
A. botulism
B. diphtheria
C. the common cold
D. measles
E. tuberculosis
A. involves fomites.
B. works only with noncommunicable diseases.
C. involves specific diseases.
D. requires direct contact.
E. requires an arthropod.
A. a healthy person
B. a sick animal
C. a sick person
D. a hospital
E. None of the answers is correct; all of these can be reservoirs of infection.
A. pus
B. water
C. a hypodermic needle
D. insects
E. droplets from a sneeze
A. The pathogen reproduces in the vector.
B. Houseflies are an important vector.
C. The pathogen may require the vector as a host.
D. The pathogen may enter the host in the vector’s feces.
E. The pathogen may be injected by the bite of the vector.
A. malaria – vector
B. influenza – droplet infection
C. salmonellosis – vehicle transmission
D. syphilis – direct contact
E. None of the pairs is mismatched.
A. droplet transmission
B. vector
C. vehicle transmission
D. indirect contact transmission
A. fomite.
B. direct contact.
C. vector.
D. vehicle transmission.
E. droplet transmission.
the situation is an example of
A. a focal infection.
B. a zoonosis.
C. a nonliving reservoir.
D. human reservoirs.
E. a vector.
The method of transmission of the disease in the situation was
A. droplet.
B. vector-borne.
C. indirect contact.
D. vehicle.
E. direct contact.
A. rabies
B. Hantavirus pulmonary syndrome
C. tapeworm
D. cat-scratch disease
E. None of the answers is correct; all of these are zoonoses.
A. always caused by pathogenic bacteria.
B. only a result of surgery.
C. always caused by medical personnel.
D. acquired during the course of hospitalization.
E. always present, but is inapparent at the time of hospitalization.
A. gram-negative cell walls
B. lack of handwashing
C. lapse in aseptic techniques
D. lack of insect control
E. antibiotic resistance
A. They may be caused by drug-resistant bacteria.
B. They may be caused by opportunists.
C. They occur in compromised patients.
D. They may be caused by normal microbiota.
E. The patient was infected before hospitalization.
A. errors in aseptic technique
B. normal microbiota on the operating room staff
C. using syringes more than once
D. antibiotic resistance
E. All of the answers are correct.
A. nosocomial infection.
B. latent infection.
C. sporadic disease.
D. communicable disease.
E. None of the answers is correct.
A. Antibiotic resistance
B. Climatic changes
C. New strains of previously known agents
D. Ease of travel
E. The emergence of infectious diseases can be attributed to all of these
A. Antimicrobial therapy for hemodialysis-associated infections increases antibiotic resistance.
B. The USA100 strain accounts for most hospital-acquired MRSA.
C. The USA300 strain accounts for most community-acquired MRSA.
D. The M in MRSA stands for mannitol.
E. S. aureus is differentiated from other mannitol+ cocci by the coagulase test.
A. ecology.
B. communicable disease.
C. morbidity and mortality.
D. epidemiology.
E. public health.
A. analytical
B. case control
C. experimental
D. descriptive
E. prodromal
A. Atlanta, GA.
B. Washington, DC.
C. New York City, NY.
D. Las Angeles, CA.
E. Chicago, IL.
West Nile virus was originally identified in 1937, when it caused a significant outbreak in Uganda. Following this initial outbreak, only minor occurrences in Egypt and Israel had been observed until 1999, when the virus reappeared with a significant outbreak in New York City. This appearance was important because it was the first time West Nile virus had been observed in the United States. Since then, West Nile virus has been declared an important pathogen to public health officials and those involved in veterinary medicine. In fact, in 2009, the CDC declared West Nile virus to be endemic in the United States.
A. West Nile virus causes an infection and death in birds such as crows and blue jays.
B. West Nile virus causes a latent viral infection that can emerge later in life.
C. West Nile virus was first isolated in Uganda in 1937 and has caused significant outbreaks every year since then.
D. West Nile virus outbreaks have increased in number and affected areas since 1937.
– An arbovirus is maintained in nature through biological transmission.
Arboviruses get their name because they are typically arthropod-borne viruses that remain in nature because of biological transmission between susceptible hosts by blood-feeding arthropods, such as mosquitoes.
Select all that apply.
– An arbovirus is an arthropod-borne virus.
– An arbovirus is a virus isolated in Ann Arbor, Michigan.
– An arbovirus is maintained in nature through biological transmission.
– An arbovirus is a virus that originated from plants.
The students tried to isolate and identify the West Nile virus from the birds because there is a high probability that the birds were infected with the virus. Birds are considered to be an amplifying host for the West Nile virus, which means that the number of viral particles is increased dramatically within this host. Although house sparrows seem to be tolerant of this amplification process, studies had shown that crows and blue jays, both of which were specimens, were susceptible to death from this virus.
A. The students tried to isolate and identify West Nile virus from birds because they are large animals. It would be difficult to isolate West Nile virus from mosquitoes because they are small.
B. The students tried to isolate and identify West Nile virus from birds because they had access to dead birds that were known to be infected with West Nile virus.
C. The students tried to isolate and identify West Nile virus from birds because they are an amplifying host for the virus, making it more likely that the virus can be isolated from these animals.
D. The students tried to isolate and identify West Nile virus from birds because it is faster to isolate the virus from a bird than to isolate it from a mosquito.
Encephalitis is an inflammation of the brain tissue. It is a concern to health care professionals because an infection in the brain means the virus has breached protective measures of the blood-brain barrier. Brain infections are serious because many are fatal because it is difficult to treat them with antimicrobials. Antimicrobials must be lipid-soluble in order to cross the blood-brain barrier. There is an exception, however. In some infections of the brain, the inflammation alters the permeability of the blood-brain barrier and may allow some antimicrobials to cross that would not be able to cross if the infection were not present.
A. Encephalitis is an inflammation of the meninges. It is a concern to health care professionals because of how quickly the infection will spread to the rest of the body.
B. Encephalitis is an inflammation of the peripheral nervous system. It is a concern to health care professionals because of how quickly the infection will spread to the rest of the body.
C. Encephalitis is an inflammation of the brain tissue. It is a concern to health care professionals because an infection in the brain means the virus has breached protective measures.
D. Encephalitis is an inflammation of the spinal cord. It is a concern to health care professionals because the infection will spread to the brain.
The best way to prevent West Nile virus infections is to limit exposure to the mosquitoes. This can be accomplished by using bug sprays, by staying indoors during times when mosquitoes are out (particularly in the summer months), and by wearing protective clothing outdoors if mosquitoes are present. Another preventative measure is to eliminate sources of water, especially stagnant water, where mosquitoes lay their eggs. This will help to decrease mosquito populations, reduce the possibility of exposure to the mosquito, and as a result limit the chance of infection with West Nile virus.
A. Kill all mosquitoes to prevent the transmission of West Nile virus.
B. Kill all birds to prevent the amplification and transmission of West Nile virus.
C. Limit exposure to mosquitoes to prevent the transmission of West Nile virus.
D. Limit exposure to birds to prevent the transmission of West Nile virus.
– West Nile virus has a high mortality rate in immunosuppressed humans and infects many species of birds in southern Europe, the Mediterranean basin, and North America.
– West Nile virus is maintained in nature through biological transmission between susceptible hosts by blood-feeding arthropods.
Emerging infectious diseases are defined as ones that are new or changing, have increased in incidence in the recent past, or show a potential to increase in the near future. Given the increase in number of cases of West Nile virus encephalitis and avian death since it appeared in New York City in 1999, this virus meets the definition of an emerging infectious disease. Over half of known emerging infectious diseases are zoonotic, mainly of viral origin, and are likely to be vector-borne. West Nile virus is all of these things, and infections with this virus must be reported to the CDC for tracking. The CDC works along with the National Institutes of Health (NIH) and the World Health Organization (WHO) to address issues related to emerging infectious diseases. Together, these agencies have set goals for investigating, monitoring, and controlling emerging infectious diseases worldwide.
Select all that apply.
– West Nile virus is an arthropod-borne virus transmitted by mosquitoes.
– West Nile virus has a high mortality rate in immunosuppressed humans and infects many species of birds in southern Europe, the Mediterranean basin, and North America.
– West Nile virus is maintained in nature through biological transmission between susceptible hosts by blood-feeding arthropods.
– West Nile virus has a positive, single-stranded RNA genome that is 11,000 to 12,000 nucleotides long.
– The pathogen must be isolated from the diseased host and grown in pure culture.
– The same pathogen must be present in every case of the disease.
– The pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animal.
You have correctly identified the four statements that describe Koch’s postulates. These experimental steps are used to systematically link a specific microbe to a specific infectious disease.
Which of statements best describe Koch’s postulates?
Select all that apply.
– The pathogen must be isolated from the inoculated animal and must be shown to be the original organism.
– The pathogen must be isolated from the diseased host and grown in pure culture.
– The same pathogen must be present in every case of the disease.
– The microscopic properties of pathogens isolated from the original (diseased) and inoculated (also, diseased) animals should differ significantly.
– The pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animal.
– Microorganism X might not be linked to Floppy Ear disease, since the inoculated mouse remained healthy.
You have correctly identified two conclusions that can be drawn from this experiment. Koch’s postulates state that the pathogen must be isolated from the diseased host, grown in pure culture, cause disease in a healthy laboratory animal, and the re-isolated microorganism be the same as original pathogen. In this scenario, the suspected pathogen did not meet all of Koch’s postulates, since the laboratory mouse did not show signs of infection.
A rabbit was found to have Floppy Ear disease that causes long-ear infections, but its etiology (cause) is unknown. Unknown Microorganism X from the infected rabbit’s right ear was successfully isolated and cultured on laboratory growth media. The ear of a healthy laboratory mouse was then inoculated with isolated microorganism, and after a period of time, no disease is observed. Which of the following statements BEST describe the conclusion(s) that can be drawn from this experiment?
Select all that apply.
– Microorganism X is the etiologic agent for Floppy Ear disease since it caused infection in the diseased rabbit.
– A laboratory mouse might not be an appropriate, susceptible host; an experiment with a laboratory rabbit may be needed.
– Microorganism X might not be linked to Floppy Ear disease, since the inoculated mouse remained healthy.
– It is not possible to isolate and culture Microorganism X in the laboratory, since this microbe is found in nature.
– Microorganism X modified its cell wall structure while being cultured, and is no longer infectious to rabbits.
– Healthy laboratory organisms rarely show signs and symptoms of infection and disease.
-Different pathogens can produce the same signs and symptoms, making it difficult to determine which microorganism is causing a disease.
-Some pathogens cause several different diseases, which makes it difficult to link one pathogen to one disease using Koch’s postulates.
-Some infectious agents have specific growth requirements that prevent it from being artificially cultured in the lab.
-The steps are designed to systematically link a pathogen to a specific infectious disease.
-Lab findings provide experimental evidence that support the germ theory of disease.
-Healthy susceptible animals can be used as model organisms when testing many types of infections, thus avoiding the unethical inoculation of healthy human hosts.