Parasitology exam 2 Flashcards

Terms Definitions
Entameoba histolytica
-intestinal lesions, hepatic amebiasis, pulmonary amebiasis, cutaneous amebiasis
-Fecally contaminated food or water
-Musca domestica - filth fly
-Fecal for trophs or cysts
-Several drugs will help
both benefit
Plasmodium falciparum
-Malignant tertian malaria
-enters all RBCs, so malignant
-Tropical climates
-50% of all human malaria
-Only one extra eurythrocytic (EE) stage
-Maurer's spots
-About 50% of human malaria
-Merozoites can reenter RBCs
synthesize with chlorophyll
Diagnosis of Notoedres
Skin scrape
Giardia lamblia
-Most common intestinal flagellate of humans
-Trophs in small intestine
-Four pairs of flagella
-Suction cup form
-more of a problem for children than adults
-interferes with fat absorption
-jaundice - bilirubin
Iodameoba beutschlii
-Commensal of colon
-sometimes associated with ectopic lesions
-Large endosome
-no chromatin
-single nucleus and glycogen vacuole
Plasmodium vivax
-Benign tertiary malaria
-refers to 3rd day after infection patient shows symptoms
-Microgametes smaller, about half as common
-Merozoites only attack young RBCs, therefore benign
Entameoba coli
-Most common intestinal ameba of humans
-Eccentric endosome
-Jagged chromatoid bars
-8-16 nuclei in metacyst
Causes Chagas' disease
T. cruzi
What are Dipylidium caninum?
Diagnosis of Cheyletiella
Scotch tapeSuperficial scraping
Diagnosis of Trombiculid mites
Clinical signsHistory
Keywords: Capillaria plica(bladder worm)
UrineNo Treatment
-Promastigotes transferred by sandfly to host
-enter reticuloendothelial tissues of liver and spleen
-become amastigotes
-Amastigotes are released and circulate, some enter other cells
-picked up by sandfly when feeding
-Replicate as promastigotes in
Genus Leishmania
Vector: sandfly 
Promastigotes from insect are infective
Promastigotes enter reticuloendothelial tissues of liver and spleen and become amastigotes called Leishman-Donovan (L-D) bodies
Amastigote release and circulate, some enter other cells

Circulating amastigotes picked up by feeding sandflies

Replicate as promastigotes in mid- and hind-gut of insect

Promastigotes move to insect esophagus and are infective

Amastigote is definitive in Leishmania
4 morphological stages of the 
Family- Trypansomatidae
nuclear division and cytoplasmic division together are called what in Emeria?
What are Gasterophilus sp.?
Horse bots.
what is free-living respiration?parasites
aerobicmostly anaerobic
What is the cat flea?
Ctenocephalides felis
Keywords for Trombiculid mites
pruritisnon species specific
Intermediate host of Dracunculus
Daphnia (freshwater crustacean)
-Trypomastigotes picked up by feeding Reduvid
-Become epimastigotes in midgut, reproduce
-Infective trypomastigotes in 10 days
-Enter vertabrate host as Reduvid feeds
-Phagocitized by monocytes
-become amastigotes, multiply, monocyte bursts, rele
Trypanosoma cruzi
Trypanosoma lewisi
Trypanosome of the genus Rattus
Vector is the rat flea: Nosopsyllus fasciatus
Rat produces ablastin, which is an antibody that inhibits reproduction of trypomastigotes
Balantidium coli
only human ciliate parasitic pathogen
similar to E. histolytica as to causing dysentery (although this is rare)
What phylum has apical complex structure involved in penetrating a host's cell. unicellular, spore-forming, and exclusively parasites
when Emieria cells undergo gametogony in GI cells, what are the zygotes called
Schistosoma mansoni
Inferior mesenteric veins (large intestine)Eggs with lateral spineIntestine and liver diseaseSnail: Biomphalaria sp
What is a mite infestation called?
Where is Trypanosoma brucei rhodesiense found?
East AFrica
Keywords: Trichuris(whip worms)
3 month prepatent periodResistant eggNot in cats
3 types of Demodectic mange
LocalizedGeneralized"Old Dog Syndrome"
Most common intestinal flagellate of humans
Giardia lamblia
The immune system of the vertebrate host, Nosopsyllus fasciatus, of the parasite T. lewisi produces a substance called ______ to counteract the parasite.
How is Toxoplasma gondi transmitted?
ingesting/inhaling oocystseating bradyzoites in steaks or inhaling oocysts in cat literunpasturized milk can hold brady & tachyzoites blood & organ transplantsinteruterine transmission
whats transmitts the whirling disease to trout?
tubefec worms
What is Elaeophora schneideri?
Aterial worm of ruminants.
What causes wart-like growths and thickened skin on the face of parakeets?
Knemidocoptes pilae.
What are some examples of diseases that fleas transmit?
What is the term for hard ticks?
What is an abstract?
synopsis of an article
define a Protozoa
single-celled organism will all structures and organelles and components like humans
What makes up the arachnid capitulum or gnathostoma?
Mouth parts
Brown Dog Tick is the vector for...
Erlichia canis
Common names of Culicoides spp.
Black gnat, no-see-ums, midge
Lice species of horses
Damalina equi & Haematopinus asini
Disease caused by Histomonas meleagridis is _______
Infectious enterohepatitis or histomoniasis 
Symptoms caused by T. cruzi
Chagoma and Romana's sign
what disease helped determine the revolutionary war?
Malignang Tertian Malaria
The migration and arrest within the tissues of the adult host with Neoascaris vitulorum is called?
Somatic migration.
What size are hookworms?
Very small 10-25 mm long.
Eimeria tenella
Only in chickens, causes bloody cecum. High morbidity, high mortality. Niche: ceca. Host defenses: shed cells, fecal express, macrophagesInfective: sporulated oocysts in feed or waterSporogony occurs OUTSIDE of host
What causes the "scaly leg" in birds?
Knemidocoptes mutans
What are the species of Mallophagans?
Bovicola ovisTrichodectes canisFelicola substrata
What does B12 do?
Vitamin B-12 gives you:Increased energy, Restored mental clarity, and help with memory loss, Reduced daily stress and irritabilitySigns of Deficiency: Chronic fatigue - macrocytic / megaloblastic anemia, Unexplained numbness or tingling of arms or legs, Anxiety and irritability, Depression, Digestive problem
Keywords for lice
Small size, 2 suborders, entire life cycle on host, host specific, Pediculosis
Deer tick is a vector for..
Lyme disease (Borrelia burgdorferi)
Signs of lice in sheep
Tags of woolLameness (foot louse)
Pathogenesis of demodectic mange
Heredity + dam transmission + depressed immunity
Vector for T. cruzi
Several bugs of reduvidae (cone-nosed bugs)
Toxoplasma gondii pathogenesis
Gut tissue quickly replaces so usually not a problem in adult cats
In brain or retina, can cause irreparable damage, but usually immunity has built up by then
Could lead to encephalitis, paralysis, or blindness
Most human cases are asymptomatic except if on immuno- suppressant drugs or HIV
Congenital: mother contractions T. gondii while pregnant, she is not immune and it crosses the placenta
Birth defects or still birth are common usually they are nerological damage. 
Can be passed by eating undercook beef, pork, or lamb
Flies, sandbozes, transfusions, transplant
Humans pick up parasite by petting cat. Flies can have it on their feet.
term for general disease chickens can get?
sick chick syndrome
Where are whipworms found?
found in cecum and large intestine.
What is the wingless fly the resembles a louse?
Sheep ked.
host specificity means....
adaptability of a species of parasite to a certain host or group of hosts...determined by genetic, immunological, physiological and/or eco factors
What forms the insect exoskeleton?
Hard chitinous plates connected by flexible membranes
Clinical signs of fleas in dogs
PruritisFlea Allergy Dermatits: tail base, ventral abdomen, medial thigh
Keywords for arthropod parasites of ruminants
WinterClose contactForequarters & tail base
Represented by flagella anterior to the nucleus, 
Where are they found?
Found in insect vector of Leishmania
How is Dientamoeba fragilis transmitted?
on the pinworm Enterobius vermicularis eggs
How is a malaria sporozoite transmitted?Then where does it travel?Then what does it become?
injected by anophelesto the liverTropozoite
What does Muellerius capillaris affect?
Sheep greater than six months old.
What are the two types of blow flies?
Lucilia and Phormic
What is the major vector of RMSF among wildlife species?
Haemaphysalis leporispalustris
What is the spinose ear tick that is found in cattle?
Otobius megnini
what is a secondary host?
may or not play a role
What is the pathology of Giardiasis?
intestinal disorders, diarrhea nad related symptoms due to malabsortption attaches with the adhesive discs
General biology of Trombiculid mites
Only larvae are parasiticAttach for a few hours, irritation lasts for days
Life cycle of Cheyletiella
Entirely on skin surface, but can live up to 10 days in environment
Have to live in 2 or more host in a parasite's lifetime
Law of Priority
the valid name of an organism is that which it was first designated;
published and described
use binary nomenclature
What two things cause the most destruction with malaria?
loss of Oxygen carrying capacityinflamation
What are the five routes of transmission in dogs and cats for hookworms?
1. Oral2. Skin penetration3. transplacental4. transmammary 5. ingestion of transport host.
What is the control of sheep ked?
population greatly reduced by shearing; insecticide treatments used for other ectoparasites also effective against it.
What is the pathology of Chagas' Disease?
chagoma (swelling, local); Romana's sign (edema on one side of the face), if early detect in blood and tissue; if later it is in the tissue and less in the blood.Causes heart and GI symptoms (mega-syndrome)
What type of bacteria is the agent of lyme disease & what animal harbors it?
Spirochete. White-footed mouse (Peromyscus leucopus)
How is toxoplasmosis gondi transmitted via intrauterine?
1st case must be while pregomost likely to transmit in 3rd trimester, but least serious
What are cutaneous larval migrans?
Name given to the dermatitis caused by larval penetration of the skin; dog hookworm larvae will penetrate human skin and migrate, leaving inflamed, ulcerated tracts; do not undergo any further migration or development in humans.
How can pigs become infected with Trichinella spiralis?
Canibalism 1. eating raw garbage2. eating rodents, etc.
What are the several species of Demodex sp?
D. bovisD. canis- most common.D. folliculorum (man)
what bio processes occur during the infective stage?
exsheathment or evagination of larvae, loss of cilia, phys/chem/pH, temp, enzymes
Why must you carefully remove bot fly larva?
Breaking it may produce an anaphylactic reaction
Three ways of transmission for the parasite Histomonas meleagridis

Gain entrance with food that raise stomach pH then they can get right pass the stomach
In eggs of nematode, Heterakis gallinarum so the worm is a definitive host.
Heterakis eggs eaten by earthworms, eggs hatch in earthworm, earthworm eaten by bird, earthworm is paratenic host
What is the encystment phase of Trichinella spiralis in humans?
May be residual muscle pain; heart problems.
What does fleas cause in animals?
Anemia, allergy to flea bites is very common.
what are some of the symptoms and bow to diagnose VL?
fever chillsID with smear, xenodiagnosis or biopsy
What is unique about the deer tick?
3 host tick1st rodent, 2nd human, 3rd host deer.
What is the systemic phase of Trichinella spiralis in humans?
7 days to 5 weeks after ingestion; fever, muscle pain and swelling, chills and sweating; can cause death in 4-6 weeks due to myositis.
describe the cysts of Giardia lamblia
axonemes and 4 nuclei (may not be all visible within a plane); found in the feces **median bodies are the remains of the flagella
what happens in the body when u get fever & sweats from Malaria?
Body loses sight of merozoite, so resets temp to 98.6 (step 2)
How are you able to distinguish between the trypomastigotes of Trypanosoma cruzi and Trypanosoma brucei?
T. cruzi are C shaped while the others are more elongated
Paragonimus egg
polycystic echinococcosis
E. vogeli
Triodontophorus spp. host?
Aberrant parasite
Right host/wrong tissue
Hookworm of swine
Globocephalus spp.
Physical characteristic of Trichinelloidea to ID
Each member of symbiosis
specialised structures for macromolecular uptake
What is the intestinal threadworm?
Very common intestinal parasitic infection
Infects ¼ of the world population, ~1 billion!
Cosmopolitan distribution but more common in tropical regions. Now rare in US.
More common in children
Fecal-oral transmission via conatminated foods or soil contaminated hands
Female adult worms with very high egg output which can survive for long periods in the soil
asexual reproduction in the host
Infection with different species results in dermal, mucocutaneous, and visceral forms of the disease.
Leishmania ssp.
Where does Cooperia sp. live?
Small intestines!
What is the "French/Fox lungworm"
Angiostrongylus vasorum
Giardia Clinical presentation
Incubation period: 7-14 days
Manifestation of infection vary widely from asymptomatic to acutely symptomatic, to chronic diarrhea with malabsorption
Weight loss, nausea, abdominal pain, steatorrhea, flatulence common
Symptomatic infection more common in children
Noninflammatory diarrhea. No blood, mucous in stool. No fever.
Type of symbiotic relationship in which one symbiont benefits while other neither benefits nor is harmed
period between infection and first appearance of eggslarvae
What kind of clinical manifestation does pinworm have? What type of organism is it?
Helminth-intestinal roundworm.
Manifestation: perianal itch.
Loa loa
loaisis, rain forests of Africa, Chrysops fly; transient "calabar swellings" on extremities w/ microfilariae in muscle, skin and eyes
Biological vector
some changes occur w/n this vector
Reservoir host
keeps parasite in the environment; perpetuates infection; usually no disease caused in this host
Any disease or parasite that is transmissible from animals to humans.
Taenia saginata is a associated with what main human food source?
Clinical Presentation of Strongiloides
Intestinal phase:
diarrhea and malabsorption (esp. in heavy infection)
Migratory phase:
granulomatous colitis, hepatomegaly, pneumonitis and eosinophilia, fever, recurrent serpentine urticarial rash, “larva currens”
Hyperinfection syndrome:
severe manifestations of above, septicemia, high mortality rate
Essentially disseminated strongyloides
Diagnosis like hookworm-look for the eggs i nthe stool
Treatment: Ivermectin, thiabendazole
Metronidazole is the drug of choice for
Facultative Myiasis
Condition resulting from fly larvae, normally free-living, that become parasitic and use a host for their development
symptoms of chronic malaria
Malnutrition, anaemia, spleen enlargement, reduces immune system
Name the medically important protozoa.
Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, Babesia, Trypanosoma spp., Microsporidia, Leishmania spp.,  Toxoplasma gondii,  Cryptosporidium spp., Plasmodium spp., Acanthamoeba,
(Emily Goes To Beths to Meet Long Time Certified Public Accountant)
Causes perianal pruritus, with diagnosis confirmed by the recovery of the eggs from the anus with scotch tape.
Pinworm (Enterobius vermicularis)Most common helminth infection in the US, often associated with day-care centers.
How do you prevent malaria?
1. reducing vector-human contact:decrease mosquito population, insecticide-impregnated bed net, insect repellant (DEET), wear long sleeves, pants at dawn, dusk, evening.2. Chemoprophylaxis: medication to prevent malaria to traveler:chloroquine susceptible malaria: take oral chloroquinine weekly.for cholorquinine resistant malaria: Atovaqone/proquanil, doxycycline, Mefloquine (Larium).
serology w/ enzyme linked assays + eggs in pet feces
Toxocara canis
Verminous annuerism
thinning of blood vessel wall and bulges and thickening due to migrating Strongylus vulgaris in cranial mesenteric artery
Clinical signs of Angiostrongylus vasorum?
Hypertension, coughing, dyspnea, exercise intolerance--looks like Dirofilaria immitis infection!
What is coccidia?
Sporozoan parasites of the intestinal tracts,,,intracellular,, sexual and asexual repro.
What makes cestodes unique concerning the food absorbtion?
Clinical presentation of enterobius vermicularis
Most infections asymptomatic
Perianal itching with subsequent sleep disturbance
Very rarely, abnormal migrations: vaginitis, appendicitis, prostatitis
Entamoeba histolytica (Protozoa)
the major cause of amebic dysentery
similar to maxima but less severe and often difficult to observe
one organism benefits and the other is unaffected
viscera larva migrans
migration of larva through viscera organs with associated fever children
Found within infected tissue as spherules that rupture to release endospores.
Coccidioides immitis(Dimorphic fungi with contraction of infection by inhalation of arthrospores from sand and soil).
What are Trichomoniasis clinical presentations?
1.Women: copious yellow/green vaginal discharge, vulvovaginitis, +/- vaginal bad odor, elevated pH (>4.5). Some have no or min. sxs.2.Men: Usually asymptomatic.
China, eat undercooked freshwater fish, hepatic problems
Opisthorchis sinesis, the chinese liver fluke; treat with Praziquantel
Diagnosis of Oxyuris?
tape around anus; put under microscope and examine
Vet Parasitology concerned with what two kingdoms?
1. Animalia: contains, Platyhelminths(flat worms, tapeworms, roundworms, leeches, insects, mites, ticks and spiders).2. Protista: contains protozoans
What are the lumen-dwelling protazoa?
1. amegae
2. Ciliate
3. Falgellates
4. Sporozoa
What is the most lethal form of Plasmodium?
P. falciparum
Thick and thin blood films
for Plasmodium, Babesia, Trypanosomes etc
occula larva migrans
larva encyst in eye and brain adults
Main clinical manifestation of Microsporidia?
Diarrhea. Mostly a problem in immunosuppressed people (HIV)
Endemic to Africa, especially along river basins, infection can result in River blindness
Oncocerca volvulus(transmitted by the blackfly, this nematode causes loss of elasticity of the skin with significant dependent edema).
What are intracellular parasitic protozoans?
Can't withstand drying in external environment. Their lifecycles don't include free environmental stages. Commonly transmitted from host to host by arthropod vectors.
few weeks after exposure have fever, cough, abdominal pain, rash, liver granuloma and urinary symptoms
acute schistosomiasis (Katayama's fever)
Clincal signs of Ostertagia infection?
Severe diarrhea; weight loss; bottle jaw; anemia; anorexia; loss of digestive function
Parasite that does no have to live on or within a host, will make visits to a host to obtain food or for other benefit.EX: Fem. mosquito sucks blood for egg develpment.
Periodic Parasite.
What worms enter through the skin without a vector/intermediates help?
1.Ancylostoma duodenale (hookworms)
2. Strongyloides stercoralis
3. Schistosoma mansoni (blood fluke)
the host in which a parasite lives as the larval and asexual stage is the
intermediate host
Clinical manifestations of Trichomonas vaginalis? How is it diagnosed in the lab?
T. vaginalis is a protozoa
Men: most are asymptomatic
Women: vaginal discharge and vulvovaginal soreness/irriation
physical exam: copious discharge, often w/ bubbles, giving it a frothy appearance. Characteristic fish-like odor.
Lab: pear shaped organisms with a characteristic twitching motility.
How do you Dx pulmonary paragonimiasis?
1. eggs in sputum, stool2. eosinophilia: nonspecific3. Antibody : EIA
What is the general parasitic life-cycle?
Human stages: 1.Infective stage 2. Maturation stage 3. replication Extra Human stages: 4 Growth and development
Txt for Difiliaria immitis?
Immiticde 2.5 mg/kg twice w/ 24 hours apart for 90% efficacy; or 3 injections for 98% efficacy but wait 1-2 months b/w 1st and 2nd injection
Where do Muellerius worms live?
In lung parenchyma of sheep and goats
Leishmaniasis is transmitted by what vector?
Sanflys inject the flagellet form, which then infect the phagocytic cells, and endothelial cells and become the non-flagellated form.
Name the stages of life for Dibothriocephalus (diphyllobothrium)-
1. egg
2. coracidium
3. procercoid
4. plerocercoid
5. adult
This is an infestation of the skin by larvae of flies (maggots). An ectoparasitic infestation.
What is myiasis? 10-7
What is the "parasitic burden"?
It is directly related to the numbers of parasites the host acquires from the environment.
How do sheep and goats get Muellerius?
From ingesting of snails/slugs with L3s
What diagnostic finding could lead you to think of an infection with schistosoma mansoni?
Non perculated embryoned eggs in stool
Infection results in subcutaneous "caliber" swellings and can be seen migrating across the eye and beneath the conjuctiva.
Loa Loa. (Transmitted by the bite of the mango fly).
What is the life cycle of African sleeping sickness?
1.Tsetse fly bites human2. Inoculates parasite in subcut pool of blood +/- erythema and chancre3. Low grade parasitemia in bloodstream and lymphatics.4. CNS dissemination (w/in wks for rhodesiense, yrs for gambiense)5. Sleeping sickness (meningoencephalitis)5.
What are eggs of Ascaris suum like?
Thick, mamillated egg (big bumps along edge)
Give a basic discription of the physical charactoristics of hymenolepis nana.
1. 4 suckers
2. 20-30 hooks
3. approx. 200 segments
4. segments are broader than long.
How do you minimize the risk of acquiring schitosomiasis?
1. Avoid fresh water swimming in endemic areas2. Decrease snail population3. better sanitation
Loa Loa causes what symptoms?
They call it an eye worm bc it moves about 1/2" per minute, sometimes move across eye just under conjuctiva.
Cause eosinophilia
Calabar swellings (fugative swellings)
allergic reactions
What is the life cycle of Clonorchis sinesis (liver fluke).
1. Infected humans pass eggs in feces, contaminate water supplies, snail infection, cercariae2. Cercariae infect fresh water fish3. Infected fish eaten by human4. Fluke dev/mature in human bile ducts
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