Phylum Nematoda 2

Question 1

Strongyloides stercoralis

Forms, symptoms, where it lives

Answer 1

infected by soil/fecal matter
All females in humans

Worm lives in human intestine

Rhabiditiform larvae - Filiform larvae - adult female

Abdominal pain ,dry cough , itchy red rash

Question 2

Strongyloides stercoralis life cycle

Answer 2

• rhabiditiform in intestine.shed in feces
  -become free living adult worms, eggs made by female, rhabditi form larvae hatch from emb egg
• develop to infective filariform .pen skin
  -via diff ways to small intestine =adult
  -female release eggs , hatch :rhabditiform
  .Auto infection in large intestine

Question 3

Ancylostoma duodenale(old world hookworm) effect

Answer 3

humans cats dogs. Suck blood ; chronic anemia and growth stunting in kids in tropics
Eggs in stool diagnosis

Question 4

Anclyostoma life cycle
(Small intest hookworm)

Answer 4

-Eggs in stool
-rhabditiform larva hatches
-filariform larvae in environ
-pen skin . Via blood vessel to heart and lung
- coughed up swallowed(alveoli to pharynx)
- in small intest adult
-attach to intest wall and suck blood

Question 5

Drancuculus medinesis( Guinea worm disease)
Africa
Definitive and intermediate host

Answer 5

Def: Human dog cat
Int: crustacean copepod cyclops

Question 6

Dranunculus life cycle

Answer 6

-drink unfiltered water that has copepods with larvae
-copepod die and release larvae
-pen stomach and intest wall
-mature into adult in abdominal cavity .
-males die . Preg female worm to skin surface yr later causing blister. Usually on foot. Ruptures . Water contact ; less pain and worm emerges and releases larvae.
- if copepod ingests then develops to infective larvae.

Question 7

Wuchereria bancrofti (thread like worm)
What is causes and by what
FILARIAL WORM

Answer 7

Biohelminth
Causes lymphatic filariasis: elephantiasis
Parasite carried by mosquito (int host)

People can get lymphedema (legs arms genitalia and breasts
Lymph tissue swelling

Question 8

Wuchereria life cycle

Answer 8

-takes blood meal and injects filarial (infective)larvae , pen into wound
-adults in lymphatics
—>make sheathed microfilariae . Migrate to lymph/blood channel

-Female mosquito ingests microfilariae in meal
-shed sheath. Pen midgut.
-migrate to proboscis

Question 9

Loa loa (eye worm)
Where and what it causes

Answer 9

Under skin
Causes loiasis
Migrates in eye and subcutaneous layer .
Calabar swelling caused.

Question 10

Loa loa life cycle

Answer 10

• Genus chrysops (deerfly) takes bloodmeal . Injects l3 larvae via wound.
  -adults in subcutaneous tissue
  -female makes sheathed microfilariae.
  -circulate blood,lungs,urine.

Deerfly takes bloodmeal
Ingests sheathed microfilariae
Lose sheath turn into l3 infective filarial larvae

Question 11

Onchocerca volvulus (river blindness)
Africa
Effect and vector

Answer 11

Visual impairment
Skin disease : nodules under skin / itching
Biohelminth
Blackflies : genus simulium

Question 12

Onchocerca life cycle

Answer 12

-black fly takes blood meal. L3 enter injected into skin
-in subcutaneous tissue ; adult filariae in nodules
-make unsheathed microfilariae
Circulate in blood
Found in skin / lymphatics of connective tissue

Black Fly takes meal . Microfil pen midgut to thoriasis then head and proboscis