Ehrlichia and Anaplasma Flashcards
After a mammalian host is infected with a vector-borne parasite, what has to happen before it becomes infectious?
- Intrinsic incubation period
The intrinsic incubation period occurs in the _____ host
- mammalian (i.e. deer)
The extrinsic incubation period occurs in the ____ host
- arthropod (i.e. tick)
The extrinsic incubation period is the time that it takes for the ______ vector to become infectious
- arthropod (tick)
Ehrlichia chafeensis infects what cell type?
- Monocytes
Ehrlichia chafeensis cause human monocytic ehrlichiosis (HME) by infecting ______
Monocytes
Anaplasma phagocytophilum infects what cell types?
- Granulocytes
Anaplasma phagocytophilum causes human granulocytic anaplasmosis (HGA) by infecting ______
granulocytes (neutrophils)
Malaria species infects _____ and liver cells
red blood cells
Babesia microti infects _____
red blood cells
Trypanosoma species infects monocytes and _______
macrophages
Leishmania species infects _____ and reticuloendothelial cells
macrophages
Ehrlichia & Anaplasma are a part of the ______ family
Rickettsia
Ehrlichia & Anaplasma are obligate intracellular, gram ____ bacteria and are ____ borne
negative; tick
The lone star tick is infected with _____
- Ehrlichia
Human monocytic ehrlichiosis (HME) causes ____ and sepsis
Fever
Where and when in the US does ehrlichiosis predominate?
- Southeast to south central US; spring and summer
Risk factors for contracting ehrlichiosis
- Hiking and other outdoor sports
- Exposure to wildlife
Vector for Ehrlichiosis
- Lone star tick (Amblyomma americanum)
Animal reservoirs for ehrlichiosis
◦White tail deer
◦Dogs
◦Coyotes
Other routes of transmission of ehrlichiosis:
◦Maternal-child
◦Blood transfusion
◦Direct contact with slaughtered deer
Human monocytic Ehrlichiosis (HME) blood smear finding
- See morulae in the monocytes; look like mulberries
- How is ehrlichiosis diagnosed by looking at serolgy?
- Indirect fluorescent antibody (IFA); compare the acute and the convalescent serology; looking backwards
- Ehrliciosis may be diagnosed by examining peripheral blood smear, ____, immunochemical staining in tissues, and mainly by _____ diagnosis
- PCR; clinical
Human granulocytic anaplasmosis (HGA) is caused by what arthropod?
- Black-legged tick or deer tick
Anaplasmosis occurs in what region of the US?
- Upper Midwest and Northeast US
High seroprevalence of anaplasmosis means that there is likely a lot of_______ transmission
- asymptomatic
Deer ticks or black-legged ticks with anaplasma may be co-infected with Borrelia (cause of Lyme’s disease) or ____
Babesia
Nosocomial transmission of _____ has been noted
Anaplasma
_____ may be transmitted person-person as seen in China
- Anaplasma
Peripheral blood smear of anaplasmosis
- Morulae seen in neutrphils in contrast to seeing morulae in monocytes in ehrlichiosis
GI symptoms are more frequent in ehrlichiosis/ anaplasmmosis
- ehrlichiosis
In ehrlichiosis and anaplasmosis, what is the incubation period?
- 1-2 weeks after bite with infected tick
Acute febrile illness is common in infections with:
- Ehrlichia and anaplasma
Between Ehrlichiosis and Anaplasmosis, which condition has a higher mortality rate and is more severe and life threatening?
- Ehrlichiosis
If you think that someone has ehrlichiosis or anaplasmosis, but you are waiting for confirmation, should you delay treatment with doxycycline?
- No, that can mean that the illness becomes serious and that may lead to hospitalization and manual ventilation and death
What is the best antibiotic to treat ehrlichiosis or anaplasmosis?
- doxycycline (which is a tetracycline); best becasue it accumulates inside of the bacteria
Trophozoites refers to what forms of protozoa?
- motile, feeding, reproducing forms
Mastigotes refers to what kind of form of protozoa?
- Flagellated
Merozoites, schizonts, gametes, oocysts all refer to what stage of protozoan development?
- Sexual stages
Peripheral blood smear of someone with babesiosis
- The Maltese cross is characteristic of babesiosis
Babesiosis is reported in what regions of the US?
- Northeast and upper midwest
What tick is the vector for babesia?
- Nymphal stage of the black-legged tick or deer tick
What is the animal reservoir for babesia?
- White-footed mouse
What may the clinical maifestations for Babesia be?
- Asymptomatic or can present with flu-like symptoms
- Hemolytic anemia
- What populations of people are at a high risk of severe, life-threatening disease when infected with babesia?
- Those without a spleen
- Immunocompromised
- Advanced age
It can be difficult to distinguish a babesia blood smear from a ______ smear due to the similarites in the trophozoite (ring stage)
plasmodium (malaria)
What are the 2 types of leishmaniasis?
- Visceral
- Cutaneous and mucocutaneous
Leishmaniases infect what cell type?
- Macrophages
What is the vector for leishmaniases?
- Female sand fly
Kala-azar (Hindi for black fever) refers to what diseases?
- visceral leishmaniases
In some regions, humans may be a reservoir for this parasitic infection along with small rodents
- leishmaniases
Other routes of transmission of visceral leishmaniasis
◦Blood transfusion
◦IV Drug use, needle sharing
◦Congenital
Clinical manifestations of visceral leishmaniasis
- Irregular bouts of fever
- Substantial weight loss
- Swelling of spleen and liver
- Serious anemia
- Untreated, fatality rate in developing countries 100% within 2 years
- Post-kala-azar dermal manifestations
Peripheral blood smear of someone with lieshmaniasis
- Infected macrophage with amastigote and kinetoblast
Visualization of the kinetoplast is important for diagnostic purposes, to be confident the patient has _________
leishmaniasis
In a bone marrow or spleen aspirate, what cells will you be looking for to have within them amastigotes for the diagnosis of leishmaniasis?
- macrophages
African trypanosomiasis is known as
- Sleeping sickness
American trypanosomiasis is known as
- Chagas disease
T. brucei causes
sleeping sickness
T. cruzi causes
- Chagas disease
Tsetse fly carries _______ and causes sleeping sickness
T. brucei
Reduviid kissing bug carries _____ and causes Chagas disease
T. cruzi
Sleeping Sickness is seen in Africa while Chaga’s disease is mainly seen in Latin America and ________
- South America
Animal reservoir of Chaga’s disease
◦armadillos, raccoons
◦also dogs, guinea pigs and rats
How does the reduviid bug transmit T. cruzi?
- It bites and then poops in the place where it bit on the person’s face normally; the parasites are in the big’s GI tract
Death due to Chagas is usaully due to _____ problems
- Cardiac
Romana’s sign is seen in what disease?
Chaga’s
In acute infection of trypanosomiasis, what will be seen on a blood smear?
- extracellular trypomastigotes
In chronic infection of trypanosomiasis, what will be seen in the bone marrow aspirate or muscle biopsy?
- Intracellular amastigotes
