Nematodes

Question 1

Tissue nematodes

Answer 1

Wuchereria bancrofti Loa loa

Question 2

Wuchereria bancrofti

Answer 2

vector-culex mosquito microfilaria have nocturnal periodicity

Question 3

cycle

Answer 3

adults mate and females produce microfilaria .They are picked by mosquito during the night-migrate to the midgut-thoracic muscles -mature fromL1-L3(filariform)-migrate to the proboscis.-During feeding the filariform are transfered to human skin-get into lymph vessles -mature-mate produce microfilaria.

Question 4

manifestations

Answer 4

lymph edema-blockage of lymph vessels by microfilaria elephantiasis-poisoning

Question 5

Podoconiosis

Answer 5

non-filarial elephantiasis -does not involvr microfilaria-minerals penetrate skin and block vessels.

Question 6

Dracunculus medinensis(guinea worm)

Answer 6

pattern involves cyclop.Transmission is by drinking contaminated water .male dies after mating

Question 7

life cycle

Answer 7

contaminated water containing cyclop which has L3 is ingested-larva is released in the stomach-penetrates intestinal wall and travels to the subcutaneous tissue-mature into adults-mate-male dies-female travels to limbs -causes blisters -protrudes and discharges the microfilaria-swims looking for cyclop-molts twice inside cyclop awaiting ingestion.

Question 8

manifestation

Answer 8

loss of eyesight,blisterd,ulceration of wound;allergic reaction.

Question 9

diagnosis

Answer 9

rise in eosinophil titre

Question 10

Loa loa(thread worm)

Answer 10

infection-loiasis also called eyeworm causes calabar swellings on skin vector-mango/deer fly from species Chrysops dimidiata. has a painful bite because it has a blunt mouth sheathed microfilaria with diurnal periodicity

Question 11

manifestations

Answer 11

calabar swellings,allerguc reaction to metabolic byproduct,pain,retinopathy,lymphadenitis.

Question 12

Onchocerca vulvus

Answer 12

vector-black fly -simulium damnosum.Diurnal periodicity.

Question 13

clinical manifestations

Answer 13

fibrous nodules on skin surfaces which form hyper and hypopigmentation after a while. skin wrinkles and thickens appears like skin of leopard or lizard. causes elephantiasis of the eye which leads to blindness.

Question 14

Askaris lumbricoides(round worm)

Answer 14

male has a curled tail with some protruding spicules for copulationwith straight posterior tail. Transmission-ingestion of food containing eggs invades the lungs. fertalize into infective stage in the soil.

Question 15

Hookworms

Answer 15

two species-Necatur americanus and ancylostoma duodenale. unembryonated eggs released -embroynated in warm moist soil. rhabditiform larva hatches in warm moist sandy soil to L1

Question 16

Ancylostoma duodenale

Answer 16

can become dormant in muscles so can be transfered from mother to child through transmammary route.

Question 17

Necatur americanus

Answer 17

can only pass through skin.

Question 18

Strongyloides stercoralis

Answer 18

facultative parasite Can autoinfect Transmission-skin penetration life cycle Parthenogenesis-females produce eggs without mating L1 molts twice in the soil into L3.

Question 19

larval migration

Answer 19

Ancylostoma braziliense,Ancylostoma caninum,Toxocara canis,Toxocara catis.

Question 20

Autoinfection

Answer 20

Taenia solium.,Stongyloides stercoralis,Enterobius vermicularis