Microbiology MC Final Exam
The agents that cause viral encephalitis can be contracted through all of the following except: contact with infected blood respiratory inhalation ingestion of contaminated water bite of an infected animal bite of a mosquito carrying a viral agent All of the above are potential routes of transmission of the agents of viral encephalitis
All of the above are potential routes of transmission of the agents of viral encephalitis
Which of the following statements is not true regarding the relationship between acne, impetigo, and folliculitis? Acne is formed from an inflamed sebaceous gland Impetigo is formed following the invasion of microbes into a small cut or abrasion in the skin All of these are considered superficial diseases of the epidermis and there are no risks of complications with any of them Folliculitis is an inflamed hair follicle All of these statements are true about acne, impetigo, and folliculitis
All of these are considered superficial diseases of the epidermis and there are no risks of complications with any of them
Which of the following statements about botulism and tetanus is FALSE? Both cause spastic paralysis Both are caused by a Clostridium organism There is currently only a vaccine for tetanus In adults, botulism is most commonly acquired by ingestion of the toxin, whereas tetanus is an infection requiring the presence of the bacteria
Both cause spastic paralysis
Meningitis is the inflammation of..? The brain the spinal cord Membranes surrounding the brain and spinal cord Brain AND spinal cord
Membranes surrounding the brain and spinal cord
In an unvaccinated community, college students are rapidly getting sick with symptoms such as fever, shock, cyanosis, and petechial rashes. The students were taken into the hospital where they got tests and labs done. Results show that the students had inflammation of the brain meninges. Based on this information, which agent was most likely causing this infection in students around campus? Neisseria meningitidis Plasmodium falciparum Bacillus anthracis one of the causes of arboviral encephalitis
Neisseria meningitidis
The causative agent of meningococcal meningitis is Neisseria meningitidis Neisseria gonorrhoeae Haemophilus influenzae serotype B Streptococcus pneumoniae
Neisseria meningitidis
What is the distinguishing factor between the botulinum toxin and the tetanospasmin toxin? The botulinum toxin is an endotoxin, while the tetanospasmin toxin is an exotoxin The botulinum toxin irreversibly binds to neurons, while the tetanospasmin toxin reversibly binds. Both toxins have the same structure and mechanism within a host, but the tetanospasmin toxin is far more potent The botulinum toxin binds to the membrane of a motor neuron and prevents release of acetylcholine, while the tetanospasmin toxin binds to the membrane of an inhibitory neuron and prevents the regulatory function of muscle contraction
The botulinum toxin binds to the membrane of a motor neuron and prevents release of acetylcholine, while the tetanospasmin toxin binds to the membrane of an inhibitory neuron and prevents the regulatory function of muscle contraction
Which of the following viral agents presents as one disease when initially acquired as a child, is maintained in the body as nucleic acid (latency), and then presents as a different disease in about a quarter of older adults? measles virus human immunodeficiency virus Epstein-Barr virus Varicella-Zoster virus
Varicella-Zoster virus
What could be a treatment option for an individual suffering from botulism? Antimicrobial mouth rinses Fecal microbiota transplant Ventilator support, antibiotics or gastric lavage surgery to repair the malfunctioning neurons
Ventilator support, antibiotics or gastric lavage
All of the following are common features of arboviral encephalitis except: Viruses initially infect the peripheral nervous system from the site of inoculation Birds or small mammals are common intermediate hosts in cycle Usually they are more severe or serious in children, the elderly, andimmunocompromised individuals Diseases are acquired by mosquito or tick bites in summer or early fall
Viruses initially infect the peripheral nervous system from the site of inoculation
Which of the following are characteristic signs of bacterial meningitis? (check all that apply) a sudden high fever nuchal rigidity (neck stiffness) a vesicular rash inflammation of the meninges decrease in white blood cells within the CSF
a sudden high fever nuchal rigidity (neck stiffness) inflammation of the meninges
Which of the following is true of most Staphylococcus skin infections (check all that apply) they are associated with pus (pyogenic) they are most commonly seen in only the very old or the very young they commonly occur as a result of infections with members of the skin microbiome they are often life-threatening if not treated they are potentially transmittable by direct contact with other individuals
all of the above
Effective treatment for necrotizing fasciitis may involve which of the following? amputation debridement intravenous antibiotics all of the above may be utilized in the effective treatment of necrotizing fasciitis
all of the above may be utilized in the effective treatment of necrotizing fasciitis
Arboviruses that cause acute encephalitis are transmitted via aersol droplets from infected individuals arthropods like mosquitoes or ticks ingestion of infected brains direct contact with infected animals
arthropods like mosquitoes or ticks
Jenna made a tunafish sandwich with tomatoes, mayonnaise, and canned tuna. Little did she know, the canned tuna was manufactured poorly, and the can was never fully sealed. 1-2 days after she ate the sandwich, she began feeling dizzy, had blurred vision, and abdominal pain. Jenna decided to go to the hospital. There, the doctors ran labs and tests where they found that the causative agent is an obligate anaerobe, forms endospores, and produces a potent toxin. What illness did Jenna acquire? botulism cholera intestinal anthrax bubonic plague tetanus
botulism
Which of the following diseases is typically acquired in adults by ingesting food that has been contaminated with preformed toxins and results in flaccid paralysis? salmonellosis botulism tetanus rabies S. aureus associated food poisoning Acute arboviral encephalitis
botulism
Which of the following features of the eye are considered protective against infectious agents? the optic nerve the iris eyelids and eyelashes the conjunctiva
eyelids and eyelashes
All parts of the skin are equally well-colonized by members of the normal microbiota. true false
false
Animals are the only known reservoir for the transmission of the agent that causes meningococcal meningitis. true false
false
Bacterial conjunctivitis can be distinguished from viral conjunctivitis because bacterial conjunctivitis causes watery discharge from the eye, whereas the discharge in viral conjuctivitis is thick and purulant (pus-like). true false
false
Bacterial conjunctivitis, but not viral conjunctivitis, is transmissible by direct and even indirect contact and is usually highly contagious. true false
false
Botulism is most commonly transmitted by human-to-human contact. true false
false
Clostridial myonecrosis can only occur as a result of a traumatic wound that breaks the skin. true false
false
Cutaneous anthrax is most likely to be transmitted through person-to-person interactions. true false
false
For almost all case of symptomatic arboviral infections, there are effective antiviral treatments available. true false
false
Gram negative bacteria are the usual causative agents of skin and soft tissue infections true false
false
Hyperexcitability, agitation, delirium, and bouts of phobias such as hydrophobia are characteristics of paralytic rabies. true false
false
Many microbes can penetrate intact skin. true false
false
Most infectious disease of the nervous system attack the peripheral nervous system. true false
false
Necrotizing fasciitis is highly contagious. true false
false
Shingles typically occurs in children under 10 years old. true false
false
Spastic paralysis is a defining characteristic of botulism. true false
false
The agent of meningococcal meningitis is transmitted between those in close quarters such as a dorm room. The only means of prevention is to stay away from those who have the disease. true false
false
While tetanus is a disease that infects the nervous system, it is really a food-borne illness that usually results from the ingestion of the toxin. true false
false
Which of the following is NOT a symptom of botulism? constipation weakness & dizziness blurry vision with fixed, dilated pupils abdominal pain fever
fever
Which skin diseases learned about in class can be caused by Staphylococcus aureus ? (check all that apply) fifth disease chickenpox folliculitis non-cystic acne impetigo cutaneous anthrax
folliculitis non-cystic acne impetigo
Inflammation, fever, and pus formation at the base of a facial hair are indicative of cystic acne caused by Propionibacterium acnes acne caused by S. aureus folliculitis caused by S. aureus impetigo caused by S. aureus
folliculitis caused by S. aureus
This contagious disease is caused by Gram-positive cocci that enter through microabrasions in the skin and presents initially as pus-filled vesicles on the face and limbs that develop from small red patches. impetigo acne cellulitis folliculitis measles
impetigo
Which disease is also known as 'floppy baby syndrome?' neonatal tetanus scalded skin syndrome human African trypanasomiasis infant botulism
infant botulism
Conjunctivitis is described as ___ infection of the eyeball a particular type of blindness caused by protozoa infection of the membrane covering of the eyeball chronic infection of the epithelial cells of the eye
infection of the membrane covering of the eyeball
Which of the following is the most common mode of transmission of the Varicella-Zoster virus, the causative agent of chickenpox? inhalation of endospores containing the virus inhalation of infected respiratory lesions or direct contact with skin lesions ingestion of virally-contaminated food contact with fomites contaminated with the virus
inhalation of infected respiratory lesions or direct contact with skin lesions
A pubescent male asks his physician about a collection of boils on the nape of his neck. Which term would the physician use to describe this infection to the patient? it is a carbuncle it is a vesicle it is a furuncle it is a pimple it is a sty
it is a carbuncle
Which of the following is NOT true about necrotizing fasciitis? it may not be entirely preventable because of the ubiquity of the causative agent surgical consultations should be sought immediately upon diagnosis if untreated, it can lead to amputation, organ failure, or shock it is very common and highly contagious all of the above are true
it is very common and highly contagious
Which of the following is a maculopapular rash disease? chickenpox measles cutaneous anthrax cystic acne
measles
What nervous system diseases is characterized by an increase in WBCs in the CSF, sudden high fever, and intense meningeal inflammation? meningitis rabies botulism acute encephalitis tetanus
meningitus
What type of skin environment do most of the bacterial members of the microbiome favor? Dry surfaces of skin moist skin folds anaerobic environments within the oily sebum the distal end of the hair shaft
moist skin folds
An early sign of which of the following is intense disproportionate pain at the site of the wound? bubonic plague measles necrotizing fasciitis rabies Lyme disease
necrotizing fasciitis
The best prevention strategy against an infection with methicillin resistant S. aureus (MRSA), or any S. aureus , is to _____ refrain from petting strange animals practice diligent personal hygiene get the MRSA vaccine avoid public showers in gyms
practice diligent personal hygiene
What combination of the toxin associated with anthrax is responsible for the swelling observed? protective antigen and lethal factor the edema factor alone the lethal factor alone protective antigen and edema factor the protective antigen alone lethal factor and edema factor
protective antigen and edema factor
The symptom of tetanus include having severe episodes of back spasms due to the unregulated of contraction the muscles. This type of paralysis is termed as: spastic paralysis contractile paralysis flaccid paralysis lockjaw paralysis
spastic paralysis
What layer of tissue does necrotizing fasciitis affect? epidermis subcutaneous tissue dermis muscle
subcutaneous tissue
What is the treatment for acute viral encephalitis? surgery antibiotics shock therapy supportive care to mitigate symptoms
supportive care to mitigate symptoms
Which of the following diseases manifests these symptoms: lock jaw, sweating, severe muscle spasms? rabies bacterial meningitis tetanus botulism arboviral encephalitis
tetanus
All of the following are true of the measles except : the infection is usually symptomatic only if the virus is contracted later in life resolution of infection confers lifelong immunity most cases will are self-limited and resolve without complications the virus is one of the most contagious known with a single case anticipated to infect up to 20 other (unvaccinated) individuals
the infection is usually symptomatic only if the virus is contracted later in life
A patient has been been sick for 3 days with a high fever and upper respiratory symptoms, including a cough, runny nose, and eye irritation. The patient has a rash that has spread from her head to her chest and is progressively getting worse. White spots (Koplik spots) are seen on the buccal mucosa of the mouth. What virus has infected this patient? the ebolavirus the measles virus Varicella-Zoster virus the Epstein-Barr virus
the measles virus
Most infectious viral skin diseases enter the host through: the GI tract breaks in the skin, hair follicles, or glands the respiratory tract the urogenital tract
the respiratory tract
Which of the following is considered normal flora of the central nervous system? coagulase-negative staphylococci Lactobacillus species Haemophilus species non-pathogenic streptococci (Streptococcus viridans) there are no normal flora of the central nervous system
there are no normal flora of the central nervous system
What of the following is not true about folliculitis? there is an effective vaccine for folliculitis the causative agent is usually a member of the genus Staphylococcus the condition occurs when bacteria invade the hair follicle and trigger an inflammatory reaction the pus formed during folliculitis is combination of neutrophils, cellular debris, and dead bacteria
there is an effective vaccine for folliculitis
Impetigo (pyoderma) can be caused by both Staphylococcus aureus and Streptococcus pyogenes and presents in anyone but is common in children during warm months. Which of the following is NOT a potential symptom of impetigo? oozing, pus-filled vesicles trachoma small, flat red patches on the skin cellulitis (erysipelas)
trachoma
This disease, caused by Chlamydia trachomatis, typically occurs in children where a patient's eyelids swell, turn inward, scar the cornea, and possibly cause blindness. cellulitis pink-eye trachoma genital chlamydia
trachoma
Which disease is the leading cause of non-traumatic blindness in humans? trachoma impetigo viral conjunctivitis pink eye
trachoma
Because they are often inhabitants of the skin and have easy access should the opportunity to invade arise, Gram positive bacteria are the most common causative agents of skin and soft tissue infection. true false
true
Botulism is associated with flaccid paralysis, while tetanus is associated with spastic paralysis true false
true
Infections of the nervous system are more easily contracted in infants because the blood-brain barrier has not completely formed yet in newborns. true false
true
Meningitis can be caused by bacterial, viral, protozoan, and fungal agents. true false
true
Necrotizing fasciitis occurs deep within the subcutaneous tissue, usually as a result of a wound. true false
true
One of the earliest signs of necrotizing fasciitis is severe pain disproportionate to the appearance of the wound. true false
true
Rabies is a zoonotic disease acquired by direct contact with an animal. true false
true
Skin infections typically arise due to a failure of the host's innate immune defenses. true false
true
Symptoms of tetanus include lock jaw, sweating, back spasms, drooling, and grouchiness. true false
true
Tetanus in adults is relatively rare is the United States. true false
true
The Varicella-Zoster virus goes latent in nerve ganglia making it impossible to completely clear the virus once infected. true false
true
The formation of a black eschar on the skin at the site of infection is an indication of cutaneous anthrax. true false
true
The nervous system is generally considered to be an axenic niche in the body, meaning it is free from microbes. true false
true
Type II necrotizing fasciitis most commonly initiates in humans following some sort of trauma (surgery, injury, etc.) true false
true
Which type of necrotizing fasciitis is considered the most common to be caused by a single microbial agent? Type I Type II Type III Type IV
type II
How can anthrax best be prevented in at-risk people? diligent hand-washing there is no way to prevent anthrax rigorous cleaning of the skin after an animal bite prophylactic antibiotic use prior to potential exposure vaccination
vaccination
The measles (rubeola) can best be prevented by vaccination wearing gloves when touching the rash of an infected person prophylactic antibiotics proper hand hygiene
vaccination
During latency, the Varicella-Zoster virus becomes established in which type of cell? within the dorsal root or trigeminal ganglia of the nervous system within the dermis of the skin within the alveolar cells of the lungs in the cardiovascular tissue of the heart
within the dorsal root or trigeminal ganglia of the nervous system
What is the approximate number of human deaths from rabies in the United States every year? over 1 million deaths over 100,000 deaths it's impossible to know because the disease is so difficult to diagnose <100 deaths over 10,000 deaths
<100 deaths
The transmission of the agent that causes tetanus requires the introduction of endospores into devitalized tissue. Why is this? in the environment, C. tetani is only found on penetrative objects that will create devitalized tissue when contacting humans devitalized tissue provides the appropriate nutrient to the bacterial agent being in devitalized tissue is the only way to avoid the human immune system C. tetani is an obligate anaerobe and requires dead (anaerobic) tissue to grow
C. tetani is an obligate anaerobe and requires dead (anaerobic) tissue to grow
A young woman was seen in the hospital due to having a severe infection spreading through her skin. Upon arrival, her skin appears blackened, and the blackened patches are severely painful. The infection appears to have originated from within the muscle. She complained of a small, but deep wound on her arm 2 weeks ago and it progressively got worse to the point where she needed to be taken to the emergency room. A Gram stain was done from bacteria within the wound, and it was found that the bacteria causing this disease was Gram-positive and rod-shaped. What is the name of the Gram-positive bacilli causing this disease? Clostridium perfringens Streptococcus pyogenes Clostridium tetani Clostridium difficile
Clostridium perfringens
How is the agent that causes anthrax most commonly transmitted? Aerosol droplets from an infected person Contact with endospores shed from an infected animal Direct contact with a lesion on an infected person Ingesting water contaminated with fecal matter
Contact with endospores shed from an infected animal
In the United States, infant botulism is the most common form of this disease. In order to prevent this, which of the following is the best advice? vaccinate everyone around the infant until the infant is old enough to also be vaccinated do not give an infant unpasteurized milk or juice Do not give infants less than 1 year of age honey ensure your infant avoids mosquito bites
Do not give infants less than 1 year of age honey
These small, white spots form on the inside of the cheeks of patients with measles during the early stages of infection. papules macules erythema migrans tonsil stones Koplik spots bubos
Koplik spots
Obligate anaerobes, like Propionibacterium acnes , found on the skin thrive in sebaceous glands because: The sebum present in sebaceous glands creates an anaerobic environment in which the bacteria can survive The exfoliative toxin helps to provide the necessary entrance into the sebaceous gland Due to the protective capsule on these organisms, they can survive in any environment The elevated oxygen levels and neutral pH help these organisms to survive
The sebum present in sebaceous glands creates an anaerobic environment in which the bacteria can survive
An attendant informs you that there is an individual in the patient room with bacterial conjunctivitis. Which of the following are you most anticipating you will see when you open the door? a 40-year old woman a 73-year old man a 6-year old boy a 24-year old man immunocompromised by AIDS
a 6-year old boy
Which person is most likely to contract meningococcal meningitis? An elderly person who lives alone A woman who lives with her husband A college student who lives in a dorm A man who lives with his two elementary age son
a college student who lives in a dorm
Impetigo would best be described as: a maculopapular rash infection a type of cellulitis a vesicular rash infection a localized pyogenic infection
a localized pyogenic infection
Who of the following is NOT likely to be regularly vaccinated against rabies virus? veterinarian lab researchers of the rabies viruses a pet owner with multiple dogs and/or cats a domesticated dog
a pet owner with multiple dogs and/or cats
Which of the following is an infection of the eyelash follicle? a carbuncle a furuncle a sty impetigo acne
a sty
A baseballplayer cut his hand while trying to prepare dinner. He had a game later that night so he did not have time to clean it as well as he would have liked. After wearing his glove over the cut for the duration of the game he noticed that the cut seemed irritated. A few days later he developed pain, tenderness, swelling and warmth in the area of the cut, followed by a high fever. Upon examination, the doctor found that the infection had spread from the cut into the soft tissue of the dermis, but hand not penetrated the superficial fascia. What is most likely occurring on his hand? clostridial myonecrosis necrotizing fasciitis impetigo cellulitis
cellulitis
A rapidly-spreading infection in the dermis and subcutaneous tissue (but not involving the fascia) that can occur even in the absence of a visible wound is impetigo shingles cellulitis septicemia meningococcal meningitis
cellulitis
If a person who has not been previously exposed to the causative agent of shingles encounters an individual with an active shingles outbreak, that person is most at risk of contracting the causative agent and developing: shingles chickenpox oral herpes folliculitis
chickenpox
Macules, papules, vesicles, pustules, and scabs are all present at the same time during what infectious disease? impetigo measles chickenpox cutaneous anthrax acne
chickenpox
Which of the following is NOT commonly associated with measles? clotting cough conjunctivitis coryzea
clotting
What is the best way to prevent arboviral encephalitis? develop effective vaccines for all encephalitis-causing arboviruses minimize contact with birds control the vectors minimize contact with horses
control the vectors
This is the most common, and least fatal, form of anthrax: gastrointestinal anthrax cutaneous anthrax pulmonary anthrax bubonic anthrax
cutaneous anthrax
Which of the following is NOT a symptom of chickenpox? rash intense itchiness diarrhea fever
diarrhea
How is the measles virus most commonly transmitted? indirect transmission via fomites direct transmission via contact with the maculopapular rash direct transmission from infected animals direct transmission via aerosol droplets
direct transmission via aerosol droplets
