Final; Parasites

Question 1

Parasitic diseases are among the most prevalent diseases where

Answer 1

in developing countries

Question 2

Parasitic infection is distinct from what

Answer 2

parasitic disease

Question 3

What is parasitic disease a consequence of

Answer 3

porlonged, repeated, or high burden infection; usually subacute or chronic, rarely fatal (although there are exceptions)

Question 4

Many parasitic infections are what

Answer 4

zoonosis; agents that infect animals

Question 5

Many human parasites require what to complete their life cycles

Answer 5

human and nonhuman hosts; humans are dead-end hosts

Question 6

What are the two types of parasites

Answer 6

protozoa (single cell)

helminths (multi-cell)

Question 7

Disease is a consequence if parasite what is too high

Answer 7

replication; only a small amount is required to initiate infection

Question 8

These are motile via flagella, parasitic form don’t have mito or golgi, most form cysts and are free living and solitary

Answer 8

mastiogophora

Question 9

This caused an infection in Milwaukee via the drinking water

Answer 9

crytosporidum

Question 10

These are mostly not motile, produce sporozoites which are important in transmission of infections, the entire group is parasitic

Answer 10

apicomplexa

Question 11

These are multicellular animals including roundworms, and flatworms, and are extracelluar protected by a cuticle

Answer 11

helminths (worms)

Question 12

In this type of host, the developmental stages take place out side of the host and in the host, the organism reaches maturity

Answer 12

definitive host

Question 13

This type of host is required for replication

Answer 13

intermediate host

Question 14

This is a non-infected asymptomatic carrier, not partaking in transmission

Answer 14

reservoir

Question 15

Most helminths cause what in humans

Answer 15

chronic infections that are tolerated by the human host

Question 16

This is NOT a consequence of parasitic replication

Answer 16

disease

Question 17

This is due to the number of parasites that the host initially acquired from the environment

Answer 17

parasitic burden

Question 18

How are parasitic infection resolved

Answer 18

not by most response, they spontaneously resolve when adult worm reaches senescence

Question 19

What are the major groups of parasitic helminths

Answer 19

flatworms

roundworms (nematodes)

Question 20

What are the subdivisions of flatworms

Answer 20

cestodes

trematodes

Question 21

What are the majority of parasitic vectors

Answer 21

arthropods; involved in key parasitic life stages

Question 22

Parasitic prevalence is dependent on what

Answer 22

local conditions favoring vector breeding

Question 23

What can be examples of reservoirs

Answer 23

humans
animals
environment (soil contaminated with parasitized feces)

Question 24

*How can the parasite gain entry

Answer 24

oral ingestion
penetration of the skin (unbroken)
arthropod0borne

Question 25

*This type of parasitic entry involves ascariasis and amebiasis

Answer 25

oral ingestion

Question 26

*This type of parasitic entry involves hookworms and schistosomes

Answer 26

penetration of the skin (unbroken)

Question 27

*This type of parasitic entry involves bite wounds (malaria) and blood transfusions possibly

Answer 27

arthropod-borne

Question 28

What is key to parasitic transmission

Answer 28

its dependent on parasitic life cycle and presence or absence of intermediate hosts; schistosomiasis required snails, they are not present in the US or Europe, therefore no schisto there

Question 29

Disease manifestation of parasites is dependent on what

Answer 29

the size of the inoculum (and it varies for different parasites) amoebiasis; large inoculum crypto; few cysts

Question 30

How are blood flukes able to evade the human antibody and cell mediated immune response

Answer 30

host plasma protein coasints

Question 31

How are trypanosomes able to evade the human antibody and cell mediated immune response

Answer 31

surface antigen variation

Question 32

How are leishmania able to evade the human antibody and cell mediated immune response

Answer 32

superoxide dismutase secretion

Question 33

The life cycle of some parasites is determined by what

Answer 33

the species and tissue tropism | duffy factor antigen required for malaria and many black africans don't have it = resistance

Question 34

These type of changes can induce stage-specific transitions

Answer 34

temperature; some parasites only like certain temperatures, dictating where they live

Question 35

Clinical damage due to parasites may be due to what

Answer 35

tissue damage effect of host response - may occur years after initial infection

Question 36

This disease is caused by a trypanosomiasis and is transmitted via the kissing bug and found only in the americas

Answer 36

chagas disease

Question 37

What are the symptoms of chagas disease

Answer 37

skin lesion swollen eyelid chronic infections = irreversible damage to organs

Question 38

Eradication of chagas disease is only successful when one or more of these treatments are employed

Answer 38

chemoprophylaxis; preventative drugs immunization field control measures

Question 39

Why is it difficult to immunize against parasites

Answer 39

many parasites coat themselves in host antigens some rearrange their surface antigens different proteins are displayed at different life cycles

Question 40

This is the most important blood cell parasitic disease

Answer 40

malaria; most important of protozoan diseases

Question 41

How many of the 156 names plasmodium protozoa are known to infect humans

Answer 41

4

Question 42

Infection and subsequent development of malaria is driven by what in the US

Answer 42

travel

Question 43

What is the only reservoir for plasmodia that can infect humans

Answer 43

infected humans

Question 44

How do plasmodia infected humans transmit malaria

Answer 44

imported to new regions | induced via blood transfusions etc.

Question 45

How is plasmodium spread in humans

Answer 45

sporocytes enter via mosquito bite and travels to liver leave liver as merozoites multiply in live and RBCs

Question 46

How does malaria induce damage

Answer 46

paroxysm; simultaneous lysis of many RBCs and release of large number of merozoites

Question 47

What can genetically predispose someone to be resistant to malaria

Answer 47

duffy blood group sickle cell anemia heterozygous individuals are carries

Question 48

This drug targets the parasites food vacuole where hemoglobin is degraded, killing the parasite, but now, many parasites are resistant

Answer 48

chloroquine

Question 49

This destroys RBCs and is endemic in the US and is transmitted the same as lyme disease

Answer 49

babesia

Question 50

What is the life cycle of babesia

Answer 50

``` merozoites injected under skin by tick RBCs invaded no liver intermediate stage lyses RBCs ticks feed on infected RBCs to keep cycle ```

Question 51

This is a common infection in humans, but disease is rare and it survives in macrophages

Answer 51

toxoplamsa

Question 52

How is toxoplasmosis transmitted

Answer 52

consumption of inadequate cooked meat or food contaminated with cat feces cyst penetrates the intestinal all and enters the blood stream

Question 53

What does toxoplasma affect

Answer 53

can cause miscarriage affects the amygdala in rats may be linked to schizophrenia in humans humans are 3 times more likely to die in a car crash

Question 54

These are small protozoans transmitted by sandflies (middle east) which are rare in NA and Europe and has reservoirs in rodents, dogs, other animals, and humans

Answer 54

leishmania

Question 55

What is the life cycle of leishmania

Answer 55

promastigote (flagellated) binds to macrophage and converts to amastigote (no flagella)

Question 56

This causes african sleeping sickness and is transmitted via the tsetse flie

Answer 56

trypanosoma brucei

Question 57

What are the reservoirs for african sleeping sickness

Answer 57

east africa; wild game | west africa; humans and domestic animals

Question 58

What illness is caused by trypanosomes (african sleeping sickness)

Answer 58

systemic and chronic in blood stream

Question 59

How does trypanosomes escape host immune detection

Answer 59

changing the dominant surface antigen | can infect for months and years

Question 60

What is significant about the intestinal and vaginal protozoa

Answer 60

its varied based upon motility and replication

Question 61

This has worldwide zoonosis with highly resistant cysts and is transmitted via ingestion of water contaminated by feces from animal carriers

Answer 61

giardia lamblia

Question 62

What are the symptoms of giardia lamblia

Answer 62

intestional protozoan mild, persistant diarrhea do not invade; inflammation

Question 63

This is a common vaginal flagellate, can cause vaginitis, can be transmitted via sex

Answer 63

trichomonas vaginalis

Question 64

This is an amoebiasis, causes destruction of host tissue (colon), transmitted via fecal-oral, and may humans carry non-pathogenic amoebas

Answer 64

entamoeba histolytica

Question 65

Hows does entamoeba histolytic invade and cause damage

Answer 65

adheres to cell receptors containing digalactose residues and kills on contact via pore forming proteins

Question 66

What is required to eradicate entamoeba histolytica

Answer 66

cell mediated immunity; circulating antibodies not important

Question 67

This is spread via zoonosis often in rural areas but also person to person via crowded urban environments

Answer 67

cryptosporidium

Question 68

How is cryptosporidium spread

Answer 68

infectious oocytes produced in intestine and spread to other animals does not invade intestinal epithelial or disseminate

Question 69

This the most frequent intestinal helminth infection (south US)

Answer 69

ascaris

Question 70

These intestinal helminths are common in temperate and tropical areas and prevalent in small children and institutions

Answer 70

pinworms

Question 71

These eggs do not require maturation outside the body and are transmitted via fecal-oral, hatch in SI cause peri-anal itching

Answer 71

enterobius

Question 72

What is the life cycle of a pinworm

Answer 72

``` person swallows egg eggs hatch in intestine larve mature to adult in a month mating females deposit eggs in anus anal scratching spreads eggs to others ```

Question 73

These penetrate the skin as filariform larvae via soil contemned with stool

Answer 73

hookworms

Question 74

What specific condition will lessen the chances of being infected via a hookworm

Answer 74

asthma

Question 75

hookworms are able to reduce what

Answer 75

allergic reactions

Question 76

How is the life cycle of the hookworm maintained

Answer 76

move from skin to heart then to lung then are either coughed or swallowed; can cause chronic anemia

Question 77

These intestinal helminths perforate the intestinal wall producing septicemia and can reinfect the same host; especially in the immunocompromised

Answer 77

strongyloides stercoralis

Question 78

These are long ribbon-like worms that can penetrate deep tissue and from infective cystic larvae and is acquired by eating raw or undercooked meat or fish

Answer 78

tapeworms

Question 79

Who is the tapeworm life cycle

Answer 79

depended on humans and cattle, infection from eating feces or beef with larvae; all human create with consumption of undercooked/raw meat

Question 80

Deep tissue infections of tapeworms produce what

Answer 80

severe diseases cysticercosis echinococcosis

Question 81

With tissue and blood helminths what are the infections like

Answer 81

asymptomatic encysted larva in striated/cardiac muscle cysts calcify but worms viable for 30 years

Question 82

How are tissue and blood helminths acquired

Answer 82

``` skin acquired each species (of schisto) has unique geographic distribution via snail intermediate host ```

Question 83

How is schisto spread in the body

Answer 83

cercariae released from snails burrow in skin of people with infected water travel to blood and via portal venous system to mature move in male/female pairs to the small/large intestine to reproduce

Question 84

What does schisto eggs induce

Answer 84

formation of granulomas that undergo fibrosis that can produce disease symptoms years later

Question 85

This is "river blindness" via black flies, elephantiasis via mosquitoes, and is not within the US due to geographic factors

Answer 85

filariasis

Question 86

Where do filariasis larvae live

Answer 86

in subcutaneous tissues