Micro lecture final 4
Which one of the following pairings is mismatched? Mycoplasma - walking pneumonia Chlamydophila - psittacosis Coxiella - Q fever Mycobacterium - whooping cough Burkholderia - melioidosis
Mycobacterium - whooping cough
Which of the following is NOT a bacterial pathogen transmitted by the bite of an animal? Bartonella henselae Plasmodium vivax Pasteurella multocida Streptobacillus None of the answers is correct; all of these bacterial infections can be transmitted by dog or cat bites.
Plasmodium vivax
What is the treatment that Dr. Clark will most likely recommend?
Praziquantel or albendazole, drugs that target eukaryotic parasites with minimal side effects in the host.
Nicole knew that these were both sexually transmitted infections caused by bacteria. Which of the following is correct regarding the causative agents for these diseases?
Treponema pallidum causes syphilis, while Neisseria gonorrhoeae causes gonorrhea.
Which of the following fungal infections results in a white, curdy discharge?
candidiasis
Which one of the following is NOT a typical symptom of influenza? fever chills diarrhea muscle aches headache
diarrhea
A possible complication of chickenpox is
encephalitis
Warts are caused by
papillomavirus
Which is true of the Mumps virus?
the portal of entry is the respiratory route
Which of the following is NOT a recognized form of anthrax?
septic
If someone develops shingles, he or she must have had_______________ earlier in life.
Chicken pox (Varicella zoster) virus
Why does Dr. Clark request stool samples for examination?
- He will have the laboratory prepare the samples for an ova and parasite (O&P) exam. Fresh or preserved stool samples can be observed microscopically for the presence of parasites or their eggs/cysts. - Tapeworms are pathogens of the gastrointestinal tract; as a natural progression of digestion some of the tapeworm pieces will be expelled along with fecal matter.
Which of the following cause(s) ringworm?
Microsporum and Epidermophyton
Which of the following pairs is mismatched? leprosy - direct contact rabies - direct contact meningococcal meningitis - respiratory route listeriosis - ingestion poliomyelitis - respiratory route
poliomyelitis - respiratory route
Each of the following is caused by prions EXCEPT rabies. sheep scrapie. kuru. bovine spongiform encephalopathy. Creutzfeldt-Jakob disease.
rabies
Which one of the following pairs is mismatched? syphilis - gram-negative spirochete chancroid - gram-negative rod Gardnerella - clue cells gonorrhea - gram-negative cocci trichomoniasis - fungus
trichomoniasis - fungus
Subacute bacterial endocarditis is commonly the result of infections initially focused on the oral cavity.
true
The varicella-zoster virus is the causative agent of chickenpox and shingles.
true
The most effective means of preventing influenza is
annual vaccination.
Which one of the following pairings is mismatched? otitis media - earache epiglottitis - sore throat pharyngitis - sore throat laryngitis - voice loss sinusitis - headache and nasal mucous
epiglottitis - sore throat
Which of the following represents the MOST LIKELY route of transmission for Michael's infection?
Foodborne - Eating undercooked, unwashed, or otherwise contaminated food that contained parasitic propagules
What disease does Paul suspect Ron might have contracted?
Rocky Mountain spotted fever
Which of the following is mismatched? Vibrio enterotoxin - secretion of Cl-, K+, and H2O Salmonella endotoxin - lyses red blood cells shiga toxin - tissue destruction ergot - gangrene aflatoxin - liver cancer
Salmonella endotoxin - lyses red blood cells
Poultry products are a likely source of infection by
Salmonella enterica.
Which of the following pairs is mismatched? Borrelia - rash and flulike brucellosis - a temperature of 40°C each evening cat-scratch disease - malignant pustule developing into septicemia toxoplasmosis - congenital brain damage tularemia - a localized infection appearing as a small ulcer
cat-scratch disease - malignant pustule developing into septicemia
Why do we see an increase in the levels of IgE antibody in Michael's serum?
IgE is the class of antibodies involved in hypersensitivities such as allergies and parasitic infections.
Why should children younger than 1 year of age NOT be fed honey?
They may contract botulism.
Which disease commonly leads to blindness in parts of the world but can be largely controlled through sanitary practices and health education?
Trachoma
Human-to-human transmission of plague is usually by
the respiratory route.
The eradication of smallpox was possible because
there are no animal reservoirs of the virus.
Dental plaque is an example of
a biofilm.
All of the following microorganisms can directly cause meningitis EXCEPT protozoa. virus. fungi. bacteria. mosquitoes.
mosquitoes.
Yellow fever
was eradicated from the U.S. in the early 1900s
The symptoms of tetanus are due to
tetanospasmin
The greatest single cause of blindness in the world is
trachoma.
Koplik spots are a diagnostic indicator of
measles
A 45-year-old man has pus-filled vesicles distributed over his back in the upper right quadrant, over his right shoulder, and upper right quadrant of his chest. His symptoms are most likely due to
varicella-zoster virus.
The primary victims of the influenza pandemic of 1918-1919 were
young adults.
The IV regimen administered by Ron's doctors is consistent with the CDC's recommendation that doxycycline be administered when RMSF is suspected. Apply your knowledge of RMSF to choose the most likely reasons behind this recommendation.
- A delay in treatment can lead to complications that include respiratory, cardiac, and renal failure. - Without prompt treatment, RMSF can have a mortality rate as high as 20%. - The symptoms of RMSF are similar to those of several other infections, making definitive diagnosis difficult. - Most tests that can definitively identify R. rickettsii are not very effective early in infection.
An indirect immunofluorescence assay is described as the CDC "gold standard serological test" for RMSF. Keeping in mind the principles behind indirect fluorescent-antibody (indirect FA) testing, which of the following characteristics contributes to its choice as the gold standard?
- Indirect FA is more sensitive than direct immunofluorescent testing. - Indirect FA will detect R. rickettsii-specific antibodies present in the patient's serum. - Indirect FA uses an antibody that reacts with any human antibody. - Indirect FA is rapid, sensitive, and specific.
Why was Dr. Clark worried about tapeworm infection in other body sites?
- When tapeworm larvae escape the stomach, they can travel to other parts of the body such as muscles, the liver, the eye, and even the brain to form cysticerci. - The presence of T. solium in the brain can result in neurocysticercosis, a serious condition which has symptoms resembling those of brain tumors or epilepsy.
RMSF results from the interactions that occur between the R. rickettsii pathogen and the host. The infection results from a coordinated series of events that ultimately result in disease. Apply your knowledge of bacterial pathogenesis and the symptoms of RMSF to predict the order of events that occur during RMSF.
1. Tick bites transmit R. rickettsii into bloodstream.Tick bites transmit R. rickettsii into bloodstream. 2. R. rickettsii travels throughout the body via the blood and lymph systems.R. rickettsii travels throughout the body via the blood and lymph systems. 3. R. rickettsii invades endothelial cells of blood vessels.R. rickettsii invades endothelial cells of blood vessels. 4. R. rickettsii multiplies within host cells.R. rickettsii multiplies within host cells. 5. Blood begins to escape from vessels as a result of increased vascular permeability.Blood begins to escape from vessels as a result of increased vascular permeability. 6. Symptoms, such as a macular rash, develop.Symptoms, such as a macular rash, develop.
What is the correct sequence of events for the life cycle of the pork tapeworm, T. solium?
1. eggs are produced 2. eggs are released 3. pigs eat grass 4. inside the intermediate host 5. the definite host
STI home test kits are still relatively new on the market. Given their newness, it is necessary to weigh the benefits and the risks to doing the tests at home. Place each statement below in the appropriate bin.
Advantage anyone can purchase and use improved communication increased treatment Disadvantage increased costs kits can make mistakes information leaks
Rickettsia rickettsii is a gram-negative, obligate intracellular pathogen. Which of the following statements about the R. rickettsii life cycle is FALSE?
After entering a host, R. rickettsii multiplies to levels high enough to successfully invade cells and establish an infection.
Nicole is very upset after receiving news that her ex-boyfriend Paul had tested positive for syphilis and gonorrhea. She makes an appointment with her physician. Nicole receives her test results, which indicate that she is positive for syphilis, but not for gonorrhea. What treatment will her doctor most likely prescribe?
Antibiotics
Thrush and vaginitis are caused by
Candida albicans.
Which of the following pairs is mismatched? Haemophilus influenzae - virulence due to capsule Cryptococcus neoformans - acid-fast rod Naegleria fowleri - causes amoebic meningoencephalitis Mycobacterium leprae - grows in armadillos Neisseria meningitidis - produces deadly endotoxins
Cryptococcus neoformans - acid-fast rod
Which of the following is mismatched? hookworm infestation - heavy infections may cause pica Echinococcus granulosus - most benign of human tapeworm infections pinworm infestation - humans ingest parasite's eggs Taenia solium - cysticerosis trichinellosis - humans eat larva of parasite in undercooked meat
Echinococcus granulosus - most benign of human tapeworm infections
The most common cause of traveler's diarrhea is
Escherichia coli.
The causative agent of chancroid is
Haemophilus ducreyi.
The at-home tests work similarly to pregnancy tests and are based on antigen-antibody reactions between the infectious agent and the patient's antibodies. Which class of antibody is most likely to give a result in the assay?
IgG
Which of the following is NOT true of acne?
It can be treated by eliminating fatty foods from the diet.
Nicole received her diagnosis at her physician's office. Which of the following procedures was most likely used by the physician to confirm her infection?
Nucleic Acid Amplification Testing (NAAT)
Which of the following pairs is mismatched? Pasteurella - cat-scratch disease Yersinia - plague Rickettsia- typhus. Borrelia - relapsing fever Streptobacillus - rat-bite fever
Pasteurella - cat-scratch disease
Several individuals who frequently swim at a local community pool have developed infections. Some have developed a skin rash and others have developed a painful infection of the outer ear canal. What is the most likely etiologic agent?
Pseudomonas aeruginosa
Which of the following is a characteristic of biological transmission from Dermacentor to a human host?
R. rickettsii is transmitted to the human host during a bite, when tick saliva enters the wound.
All of the following are normal microbiota of the skin EXCEPT Staphylococcus. Corynebacterium. Streptococcus. Propionibacterium. Micrococcus.
Streptococcus.
Which of the following organisms is most likely the causative agent of Michael's tapeworm infection?
Taenia solium
Compare the anatomy of the tapeworm (Image C) to the anatomy of the roundworm (Image D). Given that both are parasitic worms, which of the following reasons best explains why the tapeworm is flat?
Tapeworms utilize diffusion to absorb nutrients from the host's digestive system.
Which one of the following is a STI that may be confused with syphilis due to its ulcer formation on the genitalia?
chancroid (soft chancre)
An eight-year-old girl has scabs and pus-filled vesicles on her face and throat. Three weeks earlier she had visited her grandmother, who had shingles. What infection does the eight-year-old have?
chickenpox
Poliomyelitis is caused by a virus and usually leads to paralysis in those affected.
false
All of the following are characteristic of Pseudomonas aeruginosa EXCEPT resistance to many types of disinfectants and antibiotics. gram-positive cell wall. growth in moist environments. production of pyocyanin. rod-shaped.
gram-positive cell wall.
All of the following diseases are caused by arbovirus EXCEPT eastern equine encephalitis. primary amebic meningoencephalitis (PAM). St. Louis encephalitis. West Nile encephalitis. None of the answers is correct; all of these diseases are caused by arbovirus.
primary amebic meningoencephalitis (PAM).
What part of the United States is endemic for RMSF?
the Appalachian region (North Carolina, Kentucky)
All of the following are transmitted via the respiratory route EXCEPT smallpox. chickenpox. measles. tinea. rubella.
tinea.