Unit 1 - Apicomplexa Flashcards
1
Q
Common, can infect many vertebrates, and can cause multi-systemic disease…but can also be covert
A
T. gondii
2
Q
What is the definitive host of Toxoplasma gondii?
A
felidae (all cat species)
3
Q
What are the intermediate hosts for T. gondii?
A
almost all warm-blooded animals
4
Q
What are two routes of infection for T. gondii?
A
- ingestion of tissue cysts in IH (3-10 days)
- ingestion of sporulated oocysts (19-48 days)
5
Q
What protozoal stages of T. gondii can be seen in felids?
A
- sexual stages in intestine fertilization –> unsporulated oocysts shed
- asexual stages extra-intestinal
6
Q
What is the PPP (pre-patent period)?
A
time from infection until demonstration of oocysts in feces
7
Q
What is the most efficient route of infection for T. gondii?
A
ingestion of tissue cysts from intermediate hosts (3-10 days)
8
Q
When is peak oocyst shedding of T. gondii?
A
6-7 days PI
9
Q
What are the symptoms of T. gondii is adults cats?
A
usually subclinical
10
Q
What are the symptoms of T. gondii in kittens?
A
feline toxoplasmosis (concurrent infection, immunosuppression) - fever, weight loss, lethargy, dyspnea, abdominal discomfort, icterus, etc.
11
Q
What is the big picture behind T. gondii clinical signs?
A
multisystemic; primarily lungs, liver, ocular
12
Q
What effect does T. gondii have on sheep?
A
major cause of abortions in US, vertical transmission (infected offspring)
13
Q
How does T. gondii affect goats?
A
abortions, clinical toxoplasmosis (liver, kidneys, CNS), vertical transmission
14
Q
Is there a transmission risk of T. gondii for people?
A
yes; raw goat milk, undercooked meat
15
Q
How does T. gondii affect cattle and horses?
A
resistant to infection
16
Q
What does it mean if an animal is seropositive for an infection, i.e. T. gondii?
A
gives a positive result in a test of blood serum
17
Q
What about clinical toxoplasmosis and vertical transmission of T. gondii in dogs?
A
both are rare
18
Q
Will a fecal float detect T. gondii?
A
rarely detects oocysts
19
Q
How do you diagnose an active infection of T. gondii FelidDH?
A
rising titer (4-fold increase over two weeks)
20
Q
How can you diagnose T. gondii in IH?
A
clinical signs, antibody titers, PCR, histo, immunohisto
21
Q
What are the approved treatments for T. gondii?
A
no vaccines or drugs
22
Q
What are some off-label options for treating T.gondii?
A
clindamycin, sulfonamide & pyrimethamine, trimethoprim & sulfonamine
23
Q
What are the control methods of T. gondii?
A
remove feces daily, feed cats dry/canned/cooked meat only, prevent carnivorism/hunting
24
Q
What is the direct host of Neospora caninum?
A
dogs
25
What does N. caninum cause in dogs?
neuromuscular disease
26
What are the IH for N. caninum?
cattle (also, small ruminants, deer, horses, etc.)
27
What is the primary cause of cattle abortion worldwide?
N. caninum
28
What's a prevalent similarity between N. caninum and T. gondii?
excreted as unsporulated oocysts from the host, sporulates in the environment, cysts in intermediate host
29
What's the major different between T. gondii and N. caninum?
dogs can get reinfected, cats cannot
30
What is the PPP of N. caninum?
5-17 days
31
How long does it take N. caninum oocysts to sporulate in the environment?
24-72 hours
32
Once N. caninum sporulates, how many sporocysts does it have? Sporozoites?
2 sporocysts, 4 sporozoites
33
What are the 2 routes of infection for the IH?
oocyst, transplancental
34
What are the two routes of infection for the DH?
ingestion of tissue cyst, transplacental
35
Congenital infection with N. caninum leads to....
asymptomatic carriers
36
Describe the lesions seen with Neospora caninum:
focal necrosis to severe myositis in skeletal muscles
37
What are some clinical signs you might seen in a dog that's come into your clinic with Neospora caninum?
progressive hind limb paralysis, muscle atrophy, difficulty swallowing
38
When diagnosing N. caninum, what can be seen on a fecal float?
unsproulated oocysts (short period of time)
39
How do you test for N. caninum in cattle?
antibody test using serum or milk (ELISA); multiple testing (can use aborted calves - hist, PCR, ELISA)
40
What are the methods of control for N. caninum?
limited access of dogs to cattle, minimization of fecal contamination, remove aborted cattle, herd management
41
What are the approved treatments for N. caninum?
None; no Vx
42
What off-label drugs are used for treating clinical neosporosis?
clindamycin; trimethoprim sulfadiazine with pyrimethamine
43
What is the clinical significance of Hammondia?
must be distinguished from toxoplasma, neospora
44
What differentiates Hammondia from Neospora and Toxoplasma?
non-pathogenic, no extra-intestinal stage in DH, infects IH ONLY via ingestion of oocysts, infects DH ONLY via ingestion of tissue cysts
45
Hammondia heydorni DH? IH?
dogs, coyotes; herbivores
46
Hammondia hammondi DH? IH?
cat; mammals, birds
47
Hammondia site of infections for DH? IH?
DH: intestinal tract only
IH: throughout entire body
48
List the species that sporulate outside the host (5):
T. gondii, Hammondia, Isospora, Eimeria, Neospora
49
How many sporocysts does the Hammondia oocyst have? Sprozoites?
2 sporocysts; 4 sporozoites
50
In Sarcocystis spp., what is the definitive host and the intermediate host (think generally)?
predator - DH; prey - IH
51
Do Sarcocystis spp. have a direct or indirect life cycle?
indirect
52
What is the PPP of Sarcocystis in the DH?
7-14 days
53
What kind of reproduction occurs in the DH of Sarcocystis spp?
sexual - gametogony
54
What kind of reproduction occurs in the IH of Sarcocystis spp?
asexual - merogony
55
List the DH for Sarcocystis cruzi:
dogs, wolves, coyotes, raccoons, foxes, hyenas
56
List the IH for Sarcocystis cruzi:
cattle, ox, bison
57
What is the infective stage of S. cruzi to the DH:
sarcocyst (with bradyzoites)
58
What is the infective stage of S. cruzi to the IH:
oocyst/sporocysts
59
What is the route of infection of S. cruzi for the DH?
ingestion of tissue cyst (sarcocyst) containing bradyzoites
60
What is the route of infection of S. cruzi for the intermediate host?
ingestion of oocysts/sporocysts in environment
61
S. cruzi site of infection DH:
intestinal tract
62
S. cruzi site of infection IH:
extraintestinal - heart, skeletal muscle, tongue, esophagus, diaphragm
63
In its DH, S. cruzi is:
asymptomatic, no immunity
64
The clinical symptoms of S. cruzi in its IH are:
acute, anorexia, pyrexia, anemia, weight loss, abortion in final trimester
65
Diagnosing S. cruzi in IH is done using:
- clinical signs
- presence of sarcocyst on histology (up to 1 cm long, cylindrical)
- antibody detection
66
Diagnosing S. cruzi in DH is done using:
- sporocysts/oocysts on fecal float (normally JUST the free sporocysts)
- oocyst is approx. double the sporocyst size
67
Treatment of S. cruzi in the IH is:
prophylactc (amprolium, salinomycin, deccox, monensis, stenoral)
68
Control Measures against S. cruzi (4):
1. predator/prey control
2. avoid fecal contamination by carnivores
3. avoid feeding dogs uncooked meat
4. bury or incinerate dead livestock
69
What is the DH for S. neurona?
opossums
70
What are the IH for S. neurona?
armadillo, raccoon, cat, skunk, etc.
71
What is the AH for S. neurona?
horse
72
An agent of equine protozoal myeloencephalitis (EPM):
Sarcocystis neurona
73
What stage of the S. neurona lifecycle is infective to the DH?
sarcocyst (with bradyzoites) in an intermediate host
74
What stage of the S. neurona life cycle is infective to the IH?
sporocyst, oocyst
75
What stage of the S. neurona life cycle is infective to the AH?
sporocyst, oocyst
76
What is the site of infection for S. neurona in the DH?
intestinal tract
77
What is the site of infection for S. neurona in the IH?
skeletal muscle, tongue
78
What is the site of infection for S. neurona in the AH (horse)?
CNS
79
What are the clinical signs for the DH and IH of S. neurona?
none; asymptomatic
80
How do you diagnose S. neurona in the DH?
oocyst/sporocysts on fecal flotation
81
How do you diagnose S. neurona in the IH?
sarcocyst on histology, IFA. PCR
82
Describe the pathology for S. neurona in horses (AH):
gross lesion confined to neural tissue, histologically
83
What are the rule outs for S. neurona in horses (7)?
Neospora hughesi, equine herpes virus, lyme disease, west nile virus, cushing disease, Se deficiency, orthopedic lameness
84
How do you diagnose EPM in a horse (S. neurona)?
complete neurologic exam, equine CSF/blood tests (western blot, pcr, ifat, elisa)
85
What is the problem with diagnosing S. neurona in horses?
can't reproduce, varies widely, and the organism is difficult to detect
86
What are the FDA approved drugs for treating S. neurona EPM?
ponazuril, diclazuril, combo sulfadiazine and pyrimethamine
87
Can relapses occur with S. neurone EPM?
yes
88
How do you control S. neurona EPM?
protect feed/water sources from opossum
| reduce road-kill around farm
89
When are horses at increased risk for S. neurona?
summer, spring, fall; presence of opossum/wooded areas, age, stress
90
How to prevent Sarcocystis spp. infections in humans?
cook meat thoroughly, avoid fecal contamination of water/food
91
How do humans get Sarcocystis hominis infections?
beef with sarcocysts
92
How do humans get Sarcocystis suihominis infections?
pork with sarcocysts
93
Site of Cryptosporidium spp.
primarily GI (but can be seen in resp. tract; bursa/proventriculus of birds)
94
Do Cryptosporidium spp. have a direct or indirect life cycle?
direct
95
What is the infective stage of Cryptosporidium spp.?
sporulated oocyst
96
Where do Cryptosporidium spp. sporulate?
within the host
97
What are the routes of infection for Cryptosporidium spp.?
fecal-oral, autoinfection
98
How is Cryptosporidium transferred?
contaminated water/feed, aerosol, mechanical transport
99
What is the PPP for Cryptosporidium spp?
1 week of less
100
What is the PPP for Cryptosporidium parvum?
3-6 days
101
Common cause in intestinal disease in neonatal ruminants (1-4 weeks old):
Cryptosporidium parvum
102
C. parvum site of infection in cattle:
ileum
103
C. parvum PPP in cattle:
3-6 days
104
What is the Patent period of C. parvum in cattle?
1-2 weeks (self-limiting)
105
Clinical signs of C. parvum in cattle (3):
diarrhea, depression, anorexia
106
Pathology of C. parvum in cattle (5):
loss of epithelial cells, villus atrophy, dehydration, electrolyte imbalance, impaired nutrient digestion, absorption
107
Mature cattle site of infection for C. andersoni:
abomasum
108
Are there any clinical signs associated with Cryptosporidium andersoni in mature cattle?
no
109
Abomasal pathology of C. andersoni (4):
dilation of peptic glands, hypertrophy of gastric mucosa, thinning of epithelium, impaired protein digestion
110
Cryptosporidium species typically seen in puppies <6 months old:
canis
111
What's are 2 similarities between C. canis and C. felis
both are rarely associated with disease; diarrhea, anorexia, weight loss
112
For Cryptosporidium spp. diagnosis, what do you use to detect oocysts (4)?
sugar float, modified acid fast, fluorescent antibody test, PCR
113
Cryptosporidium oocyst morphology:
4-6 um, no sporocyst, 4 sporozoites, sporulates in host
114
Cryptosporidium treatment:
No efficacious tx, fluid & electrolyte replacement (maintenance)
115
Cryptosporidium control:
management strategies, clean up environment (formaldehyde & chlorine solutions, steam cleaning, dilute with washing, dessication)
116
Which Cryptosporidium species infect birds?
meleagridis (turkeys, humans), baileyi (poultry), galli (finches, chickens)
117
Hammondia oocysts have the same size range as what two other protozoans?
toxoplasma, neospora
118
What is the PPP for Hammondia?
1 week
119
How long is Hammondia patent for?
1-2 weeks
120
What is the DH for Neospora hughesi?
unkown
121
What is the IH for Neospora hughesi?
horse
122
How is N. hughesi transmitted?
transplacental
123
What are two cutaneous Leishmaniasis diseases?
tropica, Mexicana (& braziliensis)
124
What are the two visceral forms of Leishmaniasis?
donovani complex, infantum (U.S. foxhounds)
125
What is the vector for the Leishmania spp.?
sand flies
126
Vertebrate host for L. infantum in the U.S.:
foxhounds (endemic in many kennels)
127
Insect vector for L. infantum in US:
None identified
128
Reservoir host for L. infantum in US:
dogs
129
Transmission routes between dogs for L. infantum in the US:
direct vertical & horizontal (biting, behavioral, reused needles, venereally, transfusions, etc.)
130
First clinical signs of canine leishmaniasis:
facial alopecia, nodular skin lesion/ulcers
131
What is the PPP for canine leishmaniasis?
can be a very quick onset or prolonged
132
Serology for canine leishmaniasis:
IFA, ELISA, K-39-immunoassay
133
Staining locations to look for Canine leishmaniasis amastigotes:
bone marrow, lymph node aspirates, blood, touch preps
134
Detecting leishmaniasis in other hosts:
sand fly vector: promastigotes
135
What's the vector for Trypanosoma cruzi?
triatomine insect (nose/kissing bug)
136
The triatoma spp. was reported positive for what protozoa in the U.S.?
Trypanosoma cruzi
137
T. cruzi life cycle stages:
single, large mitochondria (kinetoplast), undulating membrane & single nucleus
138
What two morphologies can T. cruzi be?
either elongate with a single flagellum or rounded with a short, nonprotruding flagellum
139
Route of infection for triatomine insect:
ingest trypomastigotes in triatomine feces enter wound/mucosal membrane
140
Routes of infection for vertebrate host of T. cruzi:
1. via triatomine insect vector
2. transplacental
3. blood (transfusion, needles; organ transplant)
141
Confirmed (cultured) vertebrate hosts for T. cruzi:
dogs, opossums, wood rats, armadillos, raccons, mice, squirrels, grey fox
142
Seropositive vertebrate hosts for T. cruzi:
cats, moles, bats, feral hogs, bobcat, badger, coyotes, wild mice species
143
Dogs are a reservoir host for T. cruzi and are typically:
asymptomatic
144
Acute Chagas disease clinical signs in dogs:
10-30d; fever, anorexia, diarrhea, lethargy, enlarged organs, cardiac dysfunction, death
145
Chronic Chagas disease clinical signs in dogs:
eventual congestive heart failure
146
Latent Chagas disease clinical signs in dogs:
asymptomatic, low level infection, lasts for years
147
Can cats get Chagas disease?
yes, but extremely rare
148
How do you identify T. cruzi in blood smears?
giemsa stain: trypomastigotes (C-shape)
149
What methods of diagnostics can you use for T. cruzi?
blood smear, histo, culture (blood), serology
150
What's often seen in chagas histology/biopsy?
amastigotes in cardiac tissue
