Deck 21: Rickettsias, Chlamydias, Spirochetes, and Vibrios

Question 1

The bacterium is a common cause of bacterial gastroenteritis contracted from contaminated food, especially poultry.

A) Helicobacter pylori
B) Leptospira interrogans
C) Campylobacter jejuni
D) Vibrio cholerae
E) Vibrio parahaemolyticus

Answer 1

C

Question 2

Transovarian transmission is a process in which

A) an infected female vector transmits the pathogen to the eggs forming in its ovaries.
B) a pathogen infects the ovaries of the host.
C) the pathogen is spread from one host to the next by unprotected sexual intercourse.
D) the pathogen is transmitted from an infected male to a healthy female during mating.
E) a pathogen is transmitted to the host when the host ingests contaminated eggs.

Answer 2

A

Question 3

A patient in an urgent care clinic reports having frequent episodes of diarrhea with abdominal pain and fever for several days. The patient reports an allergy to shellfish. A recent bowel movement contains traces of blood. A fecal sample shows the presence of Gram- negative, curved, motile, urease- negative bacteria. Which of the following bacteria is most likely responsible for the patient's symptoms?

A) Vibrio parahaemolyticus
B) Chlamydia trachomatis
C) Vibrio cholerae
D) Helicobacter pylori
E) Campylobacter jejuni

Answer 3

E

Question 4

Rickettsiosis is caused by Rickettsia rickettsii, a pathogen that

A) provokes a severe immune response.
B) produces powerful exotoxins.
C) infects the lining of blood vessels and leads to leaking of plasma into tissue.
D) interferes with the host cell's Krebs cycle.
E) lyses the host's cells.

Question 5

Which of the following is the cause of the STD lymphogranuloma venereum?

A) Chlamydophila psittaci
B) Haemophilus ducreyi
C) Chlamydia trachomatis
D) Neisseria gonorrhoeae
E) Treponema pallidum

Question 6

What characteristic does Vibrio share with Salmonella?

A) Both have polar flagella.
B) Both have O polysaccharide antigens.
C) Both are spread primarily by fecal contamination.
D) Both are oxidase positive.
E) Both have similar shape.

Question 7

A gastroenteritis which usually resolves in 72 hours is contracted from eating shellfish contaminated with

A) Ehrlichia caffeensis.
B) Helicobacter pylori.
C) Vibrio parahaemolyticus.
D) Campylobacter jejuni.
E) Vibrio cholera.

Question 8

The STD characterized by three distinctly different symptomatic stages is the result of infection with

A) Treponema pallidum pallidum.
B) Leptospira interrogans.
C) Treponema pallidum pertenue.
D) Chlamydia trachomatis.
E) Treponema carateum.

Question 9

Which of the following is TRUE of spirochetes?

A) They are peritrichous.
B) They are obligate intracellular organisms.
C) They are pleomorphic.
D) They are Gram- positive.
E) They are able to penetrate a host's tissues.

Question 10

The Ixodes tick can become infected with Borrelia burgdorferi

A) only as a nymph.
B) as a larva.
C) as an adult.
D) either as a nymph or an adult.
E) either as a larva or a nymph.

Question 11

Epidemic typhus, spread by lice, is caused by

A) Ehrlichia caffeensis.
B) Rickettsia prowazekii.
C) Chlamydophila pneumonia.
D) Rickettsia typhi.
E) Chlamydophila psittaci.

Question 12

Which of the following is the correct pairing of rickettsial pathogen and vector?

A) R rickettsia; louse
B) R prowazeki; louse
C) R. typhi; tick
D) R typhi; tick
E) R. rickettsia; flea

Question 13

Infection with produces symptoms similar to RMSF, except for the rash, making it difficult to diagnose.

A) Chlamydophila psittaci
B) Anaplasma phagocytophilium
C) Vibrio vulnificus
D) Treponema carateum
E) Chlamydia trachomatis

Question 14

Which of the following is an intracellular parasite of humans that usually causes a mild pneumonia?

A) Anaplasma
B) Rickettsia typhi
C) Ehrlichia chaffeensis
D) Chlamydophila psittaci
E) Chlamydophila pneumoniae

Question 15

A young woman who was recently hiking in the mountains and discovered a tick on her torso has a fever that came on quite suddenly. She has no rash, but she develops leukopenia. Which of the following diseases is she most likely to have contracted?

A) anaplasmosis
B) scrub typhus
C) Lyme disease
D) Rocky Mountain spotted fever
E) relapsing fever

Question 16

The most important virulence factor of Vibrio cholerae is

A) its ability to survive in fresh water.
B) the fact that it is oxidase positive.
C) the presence of two axial flagella.
D) its ability to live in estuarine and marine environments all over the world.
E) its ability to produce a potent exotoxin.

Question 17

Treponema pallidum can be transmitted

A) from an infected mother to her unborn child.
B) through sexual intercourse.
C) by contact with infected fomites.
D) both by contact with infected fomites and through sexual intercourse.
E) both through sexual intercourse and from an infected mother to her unborn child.

Question 18

The emerging disease known as anaplasmosis is transmitted by

A) sand flies.
B) fleas.
C) lice.
D) ticks.
E) mites.

Question 19

Among adults Chlamydia trachomatis is an STD, but among children who are not sexually active it can cause ocular infections which may be spread

A) by contact with saliva.
B) by contact with saliva or blood.
C) by fecal contamination or respiratory droplets.
D) by fecal contamination.
E) in respiratory droplets.

Question 20

Epidemic typhus can recur many years after an initial episode; the recurrent disease is called

A) avian typhus.
B) murine typhus.
C) parrot fever.
D) Brill- Zinsser disease.
E) scrub typhus.

Question 21

Which of the following is a zoonosis caused by a spirochete?

A) bejel
B) yaws
C) pinta
D) syphilis
E) leptospirosis

Question 22

Which of the following pairs is MISMATCHED?

A) Chlamydophila psittaci; parrot fever
B) Chlamydia trachomatis; nongonococcal urethritis
C) Chlamydia trachomatis; pneumonia
D) Chlamydophila pneumonia; sinusitis
E) Chlamydophila psittaci; endocarditis

Question 23

Which of the following is the correct sequence for stages of Ehrlichia development in infected host cells?

A) initial body, morula, elementary body
B) morula, initial body, morula, elementary body
C) initial body, elementary body, morula
D) elementary body, initial body, morula
E) morula, elementary body, initial body

Question 24

What characteristic of Borrelia burgdorferi makes it an unusual bacterium?

A) It causes dermatological, cardiovascular, and neurological abnormalities, as well as arthritis.
B) It utilizes manganese instead of iron in its proteins and enzymes.
C) It is a spirochete that is larger than Treponema pallidum.
D) Infected ticks must remain on a host for 48 hours in order to spread Lyme disease.
E) Transovarian transmission of the pathogen is rare.

Question 25

Red mites (chiggers) spread among both humans and rodents.

A) Rickettsia rickettsii
B) Orientia tsutsugamushi
C) Ehrlichia chaffeensis
D) Borrelia recurrentis
E) Rickettsia typhi

Question 26

The signs and symptoms of infection with Helicobacter pylori are the result of

A) invasion by H. pylori into the mucosa of the large intestine.
B) damage to the lining of blood vessels by H. pylori.
C) invasion by H. pylori into the mucosa of the stomach.
D) the production of toxins by H. pylori in contaminated food.
E) the production of exotoxins by H. pylori in the intestines.

Question 27

Which of the following statements regarding trachoma is FALSE?

A) It leads to corneal scarring.
B) It first infects the conjunctiva and kills cells there.
C) It is the leading cause of nontraumatic blindness in humans.
D) Infants may contract the disease while passing through an infected birth canal.
E) It is most often a disease of adults who suffer from sexually transmitted chlamydia.

Question 28

Endosomes filled with multiplying chlamydia are known as

A) initial bodies.
B) morula.
C) reticulate bodies.
D) elementary bodies.
E) inclusion bodies.

Question 29

The sexually transmitted invasive form of chlamydia

A) is caused by the LGV strain of Chlamydia trachomatis.
B) is symptomatic in 85% of infected females.
C) is easily differentiated from gonorrhea.
D) never infects the baby of an infected mother during birth.
E) does not recur because of the immune response the host produces against reinfection.

Question 30

This pattern of fever is most commonly seen with

A) Lyme disease.
B) relapsing fever.
C) yaws.
D) syphilis.
E) lymphogranuloma venereum.

Question 31

Which of the following bacteria is responsible for the most common bacterial gastroenteritis in the United States, usually accompanied by frequent, bloody diarrhea?

A) Chlamydophila pneumoniae
B) Vibrio vulnificus
C) Borrelia recurrentis
D) Vibrio cholerae
E) Campylobacter jejuni

Question 32

Shortly after returning from a trip to several continents, a young man experiences episodes of fever, chills, muscle aches, and headache that recur at irregular intervals. The young man reports carrying only a large backpack and commonly staying in hostels along the way while traveling. Which of the following diseases is he likely to have?

A) yaws
B) louse- borne relapsing fever
C) anaplasmosis
D) scrub typhus
E) Lyme disease

Question 33

Rickettsia prowazekii is transmitted by

A) the human body louse Pediculus humanus.
B) the dog tick Dermacentor.
C) the cat flea Ctenocephalides felis.
D) mites of the genus Leptotrombidium.
E) the rat flea Xenopsylla cheopis.

Question 34

The intracellular parasite can infect mucous membranes in various organ systems of the body.

A) Ehrlichia caffeensis
B) Anaplasma phagocytophilium
C) Orientia tsutsugamushi
D) Chlamydia trachomatis
E) Helicobacter pylori

Question 35

The typical lesion of primary syphilis is

A) a generalized rash.
B) the development of buboes in the lymph nodes at the site of infection.
C) a painless reddened lesion called a chancre at the site of infection.
D) purulent sore throat.
E) gummas in bones, in nervous tissues, or on the skin.

Question 36

Leptospira interrogans gets its name from

A) its spiral shape.
B) the presence of two axial filaments, each of which is anchored at one end.
C) the fact that one end of the spirochete is curved like a question mark.
D) its corkscrew movement.
E) its ability to infect many wild and domestic animals.

Question 37

Sexually transmitted chlamydia is similar to infection with Yersinia pestis in that they both can produce

A) pneumonia.
B) conjunctivitis.
C) buboes.
D) urethritis.
E) pelvic inflammatory disease in females.

Question 38

Which of the following microorganisms have been referred to as energy parasites?

A) Borrelia
B) chlamydias
C) vibrios
D) spirochetes
E) rickettsias

Question 39

Which of the following causes pinta, a skin disease primarily of children, in which spirochetes are detectable in specimens from the lesions?

A) Borrelia recurrentis
B) Treponema pallidum pallidum
C) Treponema pallidum pertenue
D) Leptospira interrogans
E) Treponema carateum

Question 40

Which of the following diseases is considered an emerging disease because it was unknown before 1987?

A) Rocky Mountain spotted fever
B) human monocytic ehrlichiosis
C) Brill- Zinsser disease
D) lymphogranuloma venereum
E) murine typhus

Question 41

The normal habitat for Vibrio cholerae is (humans/animals/water).

Question 42

Wounds contaminated with Vibrio (cholera/parahaemolyticus/vulnificus) can lead to potentially fatal septicemia.

Question 43

Louse- borne relapsing fever is caused by a spirochete known as Borrelia (burgdorferi/recurrentis/species), which is capable of frequently changing its antigenic surface components.

Question 44

Leptospira interrogans exits the body in (feces/aerosols/urine).

Question 45

The reservoir for Orientia tsutsugamushi is (humans/mites/rodents).

Question 46

The infectious form of chlamydia is the (elementary/initial) body.

Question 47

The rash characteristic of RMSF starts on the (head/limbs/torso).

Question 48

Rickettsia (prowazekii/rickettsii/typhi) is fatal to its vector within 2- 3 weeks, preventing transovarian transmission.

Question 49

If the mother has (chlamydia/syphilis) at the time of birth, the pathogen can infect the newborn's eyes and may cause blindness.

Question 50

Which of the following statements regarding Ehrlichia is FALSE?

A) It is transmitted by ticks.
B) The organism reproduces inside the host's phagosomes.
C) It has three stages: elementary body, initial body, and morula.
D) It usually causes a spotted rash similar to Rocky Mountain spotted fever.
E) It is an emerging infectious disease.

Question 51

A nonvenereal treponemal disease transmitted by contaminated eating utensils and primarily affects children in Africa, Asia, and Australia is known as (bejel/pinta/yaws).

Question 52

Scrub typhus is transmitted to humans by mites infected with (Anaplasma/Orientia/Rickettsia).

Question 53

Which of the following pairs is MISMATCHED?

A) reticulate bodies; large variable shape
B) elementary bodies; small cocci
C) elementary bodies; dormant noninfectious form
D) reticulate bodies; replicate via binary fission in endosomes
E) inclusion bodies; RB filled endosomes

Question 54

The characteristic lesion for tertiary syphilis is the presence of (gummas/necrosis/granulomas) in bones, in nervous tissue, or on the skin.

Question 55

Gastritis from infection of the stomach wall with _ can cause inflammation leading to peptic ulcers.

A) Anaplasma phagocytophilium
B) Helicobacter pylori
C) Borrelia recurrentis
D) Rickettsia rickettsii
E) Campylobacter jejuni

Question 56

Borrelia burgdorferi is an unusual bacterium that lacks iron- containing enzymes and proteins and causes (Brill- Zinser/Lyme/RMSF) disease in humans.

Question 57

Parrot fever, caused by , is usually a pneumonia- like disease but can sometimes lead to hepatitis or endocarditis.

A) Rickettsia prowazekii
B) Chlamydia trachomatis
C) Chlamydophila pneumoniae
D) Orientia tsutsugamushi
E) Chlamydophila psittaci

Question 58

A disease of birds that can be transmitted to humans is (campylobacteriosis/Lyme/ornithosis).

Question 59

Which of the following statements concerning the causative agent of syphilis is TRUE?

A) It is a non- motile comma- shaped bacterium.
B) It is an intracellular parasite.
C) It is pleomorphic and motile by means of gliding motility.
D) It is a large bacillus with peritrichous flagella.
E) It is a large helically coiled bacterium motile by means of endoflagella.

Question 60

Major pandemics of severe diarrheal disease have been caused by Vibrio
(cholerae/parahaemolyticus/vulnificus) for centuries.

Question 61

The cholera toxin is a potent exotoxin composed of five identical B subunits and one A subunit.

Question 62

Vibrio vulnificus causes septicemia that is self- limiting and rarely fatal.

Question 63

All stages of Ixodes, the vector for Lyme disease, may feed on humans.

Question 64

Humans are the only hosts of Rickettsia rickettsii.

Question 65

A positive urease test in cultures from gastric secretions is definite identification of Helicobacter pylori.

Question 66

Small doses of antimicrobial agents are very effective in treating the late stages of Borrelia infection because most of the symptoms result from immune responses.

Question 67

Chlamydophila pneumoniae is suspected of causing arteriosclerosis.

Question 68

Relapsing fever is characterized by recurring episodes of fever and septicemia separated by symptom- free intervals. What causes this pattern?

Question 69

Explain what is meant by describing chlamydias as "energy parasites."

Question 70

All of the rickettsias are zoonoses.

Question 71

Campylobacter gastroenteritis is usually caused by ingestion of contaminated poultry.

Question 72

Compare and contrast the pathogenesis of the sexually transmitted diseases chlamydia and syphilis.

Question 73

An expanding rash that resembles a bull's- eye is characteristic of secondary syphilis.

Question 74

Explain why modern treatment of a peptic ulcer includes administering an antibacterial agent.

Question 75

A patient was admitted to the emergency department suffering from severe diarrhea and weight loss. On examination, his stool had a "rice- water" appearance. What pathogen is likely causing this condition, and how does it cause disease?