STUDY GUIDE-Animal Parasitology

Chapters 26-32

 

 

Warning:  These questions are only a guide, they are not meant to take the place of reading the text and studying the class notes.  You are responsible for the material covered in class even though I may have forgotten to cover it in this study guide.

 

 

Chapter 26

 

Ascaris

 

What is the species that most commonly infects man?

What is the size of this species? 

How many eggs may be present inside a female? 

How many eggs may a female lay each day?

Adults live where in the body of the host?

What stage is infective to the host?

What route do the juvenile worms take to finally reach the intestine of the host and become mature worms?

What climatic conditions favor transmission of this parasite?

How many people are infected worldwide?

Among humans, what group is most affected by these worms?

What are two methods of transmission of this worm?

What is ascaris pneumonitis?

What pathological conditions are caused by large numbers of worms in the intestine?

What do these worms eat?

How are these worms diagnosed?

What is the treatment?

How can infections be prevented?

 

 

Toxocara

 

What is the species of the ascarid parasite of dogs?

How do puppies become infected with this worm before they are born?

How might these parasites be transmitted to man?

What is visceral larval migrans?

What species of worms are a common cause of human visceral larval migrans?

 

 

Anisakis

                                

What is the genus of worm that is a parasite of marine fishes and poses a human health risk when these fishes are eaten raw?

What kinds of food preparations might be at risk for harboring this nematode?

 

Chapter 27

 

Enterobius vermicularis

 

What is the common name of this worm?

What are the hosts for this worm?  What group of humans is most affected by this worm?

How many people are infected by this worm?

What morphological feature is distinctive for the female of this worm?

What do these worms eat?

Where are mature females of this worm found (specifically)?

Where do females lay their eggs?  How long does it take for eggs to become infective?

What morphological form is infective to man?  How does man become infected?

Define retroinfection?  Contrast it with autoinfection?

What is self-infection?  Cross infection?

Under what settings (situations) is transmission of this worm enhanced?

What unusual technique is used to collect eggs of this worm?

How are these worms diagnosed?

What is the treatment?

How can infections be prevented?

 

 

Chapter 29

 

The filarial worms

 

Filarial worms belong to what nematode family?

Where are adults of these worms found in the body of the host?

Females of these worms deposit what kind of offspring?

How are these offspring related to the usual J1 or rhabditiform form of nematodes?

The filarial worms all employ what kind of intermediate host?

What life cycle stages are found in the intermediate host?

How are the infective stages introduced into the host?

What is the infective stage of these worms?

What is periodicity?

 

Elephantiasis

 

What species causes elephantiasis?

In elephantiasis, adults live where in the body of the host?

What is the vector (or intermediate host) for elephantiasis?

Where in the world is elephantiasis found?

The intermediate hosts for elephantiasis feed mainly during what part of the day?

What are the three phases of disease in elephantiasis?  

Each phase is characterized by what position of the worm in the host and what physiological response of the host?

What causes the elephantoid condition?  How commonly is this condition found among people infected with this worm?

How are these worms diagnosed?

What is the treatment?

How can infections be prevented?

 

River blindness

 

What species causes river blindness?  What is another common name for the same disease?

Where are adult worms of this species found in the body of the host?  The specific places where these worms are found are called what?

Where are the microfilaria of these worms found?

What is the vector (or intermediate host) for this worm?

How many cases worldwide?  Where in the world are these infections found?

Why is this disease called river blindness?

How are these worms diagnosed?

What is the treatment?

How can infections be prevented?

 

Loa loa

 

The common name for Loa loa is what?

What are the known hosts for this worm?

Where do adults of this worm live in the body of the host?

Microfilaria are found where during the day, where during the night?

What is the vector (or intermediate host) for this worm?

How many people are infected worldwide?  Where are most cases found?

Typical symptoms of this worm include a transient, painful subcutaneous swelling called what?

How are these worms diagnosed?

What is the treatment?

How can infections be prevented?

 

Dog heartworm

 

The dog heartworm is what species?

Where do adults of this worm live in the body of the host?

What is the vector (or intermediate host) for this worm?

How long does it take for the juveniles to develop into adults in the host?

What is the treatment for the juvenile stages of this parasite?

 

 

Chapter 30

 

Dracunculus medinensis

 

The common names for this worm are what?

How long are adult females? Adult males?

Where do adults of this worm (before females become gravid) live in the body of the host?

Where are gravis females found?

Females produce what kind of lesion on the skin of the host?

The female releases what life cycle stage?  Under what conditions does she release them?

What is the intermediate host for this worm?  What genus?

How does a host become infected with this worm?

What conditions must be met to allow human infections of this worm?

How are these worms diagnosed?

What is the treatment?

How can infections be prevented?

 

 

Chapter 31

 

Phylum Acanthocephala

 

What does the name Acanthocephala mean?

What are the usual hosts for these worms?

What morphological characters reflect or indicate that it is adapted for a parasitic life?

What are the morphological regions of this parasite?

What phylum are the acanthocephalans in?

What morphological characters are useful in identifying species of acanthocephala?

What kind of body covering do these worms have?

What structures in the body covering can be used to help identify some of these worms?

What unusual structures are found in males of these worms?

What do the males do to the females after copulation (so that another male cannot mate with her)?

How many testes do males have?

How many ovaries do females have?

What happens to the female ovary as the worm matures and copulates?

What unique structure do the females have that sort eggs?

What are the life cycle stages of these worms?

What are the hosts of each life cycle stage?

What is the nature of the damage caused by the adult of these worms?

How could humans become infected with these worms?

What is the source of nourishment for these worms?

 

 

Chapter 32

 

Phylum Pentastomida

 

Pentastomes are usually parasites of what animals?

What are the morphological characters of these worms?

What is the body covering of these worms?

What specialized attachment appendages do they have  and where are they found on the body?

What kind of digestive system do they have?

What do pentastomes eat?

What are the life cycle stages of this parasite?

What hosts are used for the intermediate stages?

What is the name of the species that is found in canines?  What is the intermediate host for this species?

How do humans become infected with this parasite? (two types of infection)

Are members of this group found in Puerto Rico?  If so what is the final host and what is the intermediate host?

What animals in the distant past were infected by these parasites?