CHAPTER 26:
1.) Morulae (intracellular inclusions in leukocytes) are characteristic of which of the following
diseases?
A. Malaria caused by Plasmodiumfalciparum infection but not Plasmodiummalariae
infection
B. Dengue
C. Babesia infection
D. Ehrlichiae infection
E. Loa loa
Answer: D. Ehrlichiae infects circulating leukocytes, erythrocytes and platelets where
they multiply within phagocytic vacuoles forming clusters with inclusion –like
appearance called morulae which comes from the word mulberry.
2.) Which of the following statements about epidemic typhus (Rickettsiaprowazekii disease)
is most correct?
A. The disease occurs primarily in sub-Saharan Africa.
B. It is transmitted by ticks.
C. Mice are the reservoir.
D. Historically, the disease occurs in times of prosperity.
E. Recrudescence can occur many years after the initial infection.
Answer: E. This occurs after the person has recovered from epidemic typhus and
reactivation of the Rickettsiaprowazekii. The Rickettsia can remain latent and reactivate
months or years later with symptoms similar to or even identical to the original attack of
typhus. The recrudescence of epidemic typhus is called Brill-Zinsser disease.
3.) The most useful drug to treat Ehrlichiosis is
A. Doxycycline
B. Penicillin G
C. Trimethoprim- sulfamethoxazole
D. Gentamicin
E. Nitrofurantoin
Answer: A. Tetracycline in the form of Doxycycline is cidal for Ehrlichiae and is the
treatment of choice. Therapy is administered for 5-14 days.
, later on their extremities. Some of the people had coughs. One elderly person, although
sick, was much less sick than other adults. The people huddled together to keep warm;
body lice were common. Which of the following statements is most correct?
A. The disease that these people had is common in the Rocky Mountain states.
B. The elderly person may have had acute epidemic typhus many years ago and
recrudescent typhus now.
C. Fleas from the rodents in the house were spreading Rickettsia typhi.
D. The primary host of the body louse infecting the people is the rat.
E. Epidemic typhus can be prevented by a vaccine.
Answer: B. The Rickettsiae can persist for many years in the lymph nodes of an
individual without any symptoms. Humans themselves are the reservoir of the
Rickettsiae of epidemic typhus. Brill-Zinsser disease occurs in local populations of typhus
areas as well as in persons who migrate from such areas to places where the disease
does not exist. Antibodies arise earlier and IgG rather than IgM detected after primary
infection. This early IgG antibody response and the mild course of the disease suggest
that partial immunity is present from the primary infection.
5.) Which of the following statements about Ehrlichiae and ehrlichiosis is most correct?
A. Dogs and mice are reservoirs.
B. Mosquitoes are the vectors.
C. Ampicillin is the treatment of choice.
D. Culture is a good method to confirm the diagnosis.
E. Ehrlichiae are typically found in lymphocytes.
Answer: A. Ehrlichiae infects the monocytes not lymphocytes. Ticks are the vectors not
mosquitoes. Doxycycline is the treatment of choice for Ehrlichiae. Serological tests are
the good methods to confirm the diagnosis not culture. All the choices except for A are
false.
1.) Morulae (intracellular inclusions in leukocytes) are characteristic of which of the following
diseases?
A. Malaria caused by Plasmodiumfalciparum infection but not Plasmodiummalariae
infection
B. Dengue
C. Babesia infection
D. Ehrlichiae infection
E. Loa loa
Answer: D. Ehrlichiae infects circulating leukocytes, erythrocytes and platelets where
they multiply within phagocytic vacuoles forming clusters with inclusion –like
appearance called morulae which comes from the word mulberry.
2.) Which of the following statements about epidemic typhus (Rickettsiaprowazekii disease)
is most correct?
A. The disease occurs primarily in sub-Saharan Africa.
B. It is transmitted by ticks.
C. Mice are the reservoir.
D. Historically, the disease occurs in times of prosperity.
E. Recrudescence can occur many years after the initial infection.
Answer: E. This occurs after the person has recovered from epidemic typhus and
reactivation of the Rickettsiaprowazekii. The Rickettsia can remain latent and reactivate
months or years later with symptoms similar to or even identical to the original attack of
typhus. The recrudescence of epidemic typhus is called Brill-Zinsser disease.
3.) The most useful drug to treat Ehrlichiosis is
A. Doxycycline
B. Penicillin G
C. Trimethoprim- sulfamethoxazole
D. Gentamicin
E. Nitrofurantoin
Answer: A. Tetracycline in the form of Doxycycline is cidal for Ehrlichiae and is the
treatment of choice. Therapy is administered for 5-14 days.
, later on their extremities. Some of the people had coughs. One elderly person, although
sick, was much less sick than other adults. The people huddled together to keep warm;
body lice were common. Which of the following statements is most correct?
A. The disease that these people had is common in the Rocky Mountain states.
B. The elderly person may have had acute epidemic typhus many years ago and
recrudescent typhus now.
C. Fleas from the rodents in the house were spreading Rickettsia typhi.
D. The primary host of the body louse infecting the people is the rat.
E. Epidemic typhus can be prevented by a vaccine.
Answer: B. The Rickettsiae can persist for many years in the lymph nodes of an
individual without any symptoms. Humans themselves are the reservoir of the
Rickettsiae of epidemic typhus. Brill-Zinsser disease occurs in local populations of typhus
areas as well as in persons who migrate from such areas to places where the disease
does not exist. Antibodies arise earlier and IgG rather than IgM detected after primary
infection. This early IgG antibody response and the mild course of the disease suggest
that partial immunity is present from the primary infection.
5.) Which of the following statements about Ehrlichiae and ehrlichiosis is most correct?
A. Dogs and mice are reservoirs.
B. Mosquitoes are the vectors.
C. Ampicillin is the treatment of choice.
D. Culture is a good method to confirm the diagnosis.
E. Ehrlichiae are typically found in lymphocytes.
Answer: A. Ehrlichiae infects the monocytes not lymphocytes. Ticks are the vectors not
mosquitoes. Doxycycline is the treatment of choice for Ehrlichiae. Serological tests are
the good methods to confirm the diagnosis not culture. All the choices except for A are
false.
