Human Parasitic Helminthes人體寄生蠕蟲

NEMATODA (Roundworms) 線蟲

TREMATODA (Flukes) 吸蟲

CESTODA (Tapeworms) 絛蟲

Nemathelminthes 線形蠕蟲Platyhelminthes 扁平蠕蟲

Class Trematoda 吸蟲綱

Phylum Platyhelminthes 扁形蟲門

Subclass:- Aspidogastrea 盾腹亞綱

- Monogenea 單殖亞綱- Digenea 複殖亞綱 (Greek: Dis - double, Genos - race)

1 cm

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1. H. heterophyes異形異形吸蟲2. O. felineus貓肝吸蟲3. C. sinensis中華肝吸蟲4. P. westermani衛氏肺吸蟲5. F. hepatica牛羊肝吸蟲6. F. buski薑片蟲

複殖亞綱吸蟲形態特徵及基本構造

腸道

口吸盤

睪丸

卵巢

卵黃腺

子宮

腹吸盤

具神經系統、排泄系統、消化系統及雌雄生殖系統 (Monoecious)－血吸蟲除外

內部構造

吸盤 均具口吸盤(攝取食物)及腹吸盤(附著器官)

體腔 無體腔

形態扁平長形呈葉狀，不分節。長度由2mm至80mm。表皮有棘、結節或塉狀突起

Cephalic ganglia頭神經節Ventral nerve truck腹神經斡Lateral nerve trunk側神經斡Dorsal nerve trunk背神經斡

口吸盤口吸盤

腹吸盤

腸道

吸蟲消化系統

吸蟲排泄系統

食道及咽

盲腸

排泄小管焰細胞 焰細胞

排泄小管

排泄囊/排泄孔

吸蟲神經系統

腹吸盤

血吸蟲

吸蟲

總生殖室Common genital atrium

Uterus 子宮

Egg卵

Mehlis gland卵殼腺Ootype呈卵腔

Vitelline duct 卵黃管

Seminal receptable 受精囊

Laurer’s gland 勞氏管Ovary 卵巢

口吸盤 Oral sucker

生殖孔 Genital pore陰莖 Cirrus陰莖囊 Cirrus sac

前列腺 Prosate gland儲精囊 Seminal vesicle輸精管 vas deferens卵黃腺 Vitelline gland卵黃管 Vitelline duct

輸出管 vas efferentia

睪丸 testis

吸蟲生殖系統—雌雄同體 (Monoecious)

腸道

口吸盤

睪丸

卵巢

子宮

腹吸盤

卵黃腺

C. sinensis中華肝吸蟲

M. yokogawi橫川異形吸蟲

F. buski薑片蟲

Echinostoma spp.棘口吸蟲

卵蓋

● Asexual Generation 無性生殖世代Multiplication of sporocyst or redia in 1st I.H.雷氏幼蟲或胞子幼蟲（血吸蟲）在中間宿主繁殖

Reproduction & Life Cycle

All flukes are oviparous (lay eggs)Eggs of all flukes, except for Schistosoma spp. are

operculated.所有吸蟲之蟲卵均具卵蓋（除血吸蟲外）

Cross-fertilization異體受精

Self fertilization自體受精

ORAND

● Sexual Generation 有性生殖世代Production of eggs by adults in final host 成蟲在終宿主產卵

General Trematode Life Cycle

1st Intermediate Host第一中間宿主淡水螺類

2nd Intermediate Host第二中間宿主

甲殼類 Crustacean水生植物 Water plants

魚類 Fishes昆蟲 Insects

Sporocyst胞子幼蟲

Miracidium纖毛幼蟲

Cercaria尾動幼蟲

Redia雷氏幼蟲

Final Host 終宿主Mammals

HumanAdult worm成蟲

Egg蟲卵 進入水中蜉化或被螺類吞食

Metaceraria囊狀幼蟲

有性生殖期

診斷期

感染期

無性生殖期

吸蟲食譜大全

Egg (蟲卵)

• The egg contains an embryo rather than an oocyte• Eggs are shed at different degrees of maturity by different flukes• Eggs have to leave the body of the final host to continue development• The mature miracidium within the egg uses light, osmolarity and temperature

as clues to when hatching is appropriate• Hatching proceeds in most species through a preformed “door” the operculum

General Trematode Life Cycle

牛羊肝吸蟲 衛氏肺吸蟲 中華肝吸蟲 曼森血吸蟲

Miracidium (纖毛幼蟲)• The miracidium is highly motile due

to the cilia on its surface• Miracidia have simple eyes (they

avoid light) and several chemical and mechanical receptors which they use to find the intermediate snail host

• Penetration glands secrete proteases and other lytic enzymes on contact with appropriate host

• Miracidia of flukes use land snails as intermediate host will hatch upon ingestion by the snail and penetrate the gut epithelium

General Trematode Life Cycle

Sporocyst (胞子幼蟲)

• After penetration the miracidum undergoes metamorphosis into the sporocysts

• This stage has most organ systems reduced to the bare minimum and acts as a germinal sac (germ ball)

• The sporocyst takes up nutrients only over its tegument and the germinal mass expands and develops into

daughter sporocysts, redia or cercaria

General Trematode Life Cycle

胚球子胞子幼蟲雷氏幼蟲尾動幼蟲

胚細胞球(胚球)

子胞子幼蟲

Redia (雷氏幼蟲)• Sporocyst can produce cercaria or a next

amplification generation the redia• Redia have features of the adult fluke like

oral and ventral sucker, a gut and “birth pore” to release cercaria

• Redia are mobile in the snail and can prey on sporocysts and redia of the same or other species (competition)

General Trematode Life Cycle

尾動幼蟲

Cercaria (尾動幼蟲)• Cercaria are the stages that leave the

intermediate host and infect the final host• There can be many consecutive waves of

“shedding” from the snail• Cercaria already show many anatomical

features of the adult fluke

General Trematode Life Cycle

Metacercaria (囊狀幼蟲)• Reflecting the ecology of their hosts cercaria have

developed an array of adaptations to achieve successful infection

• Encystation within the muscle of intermediate hosts e.g. metacercaria in fish (Clonorchis)

• Encystation on plants (Fasciola)• Direct penetration of host skin upon water contact

(Schistosoma)

General Trematode Life Cycle

囊狀幼蟲

Intestinal Flukes 腸吸蟲Fasciolopesis buski 布氏薑片蟲Metagonimus yokogawi 橫川異形吸蟲Heterophyes heterophyes 異形異形吸蟲Echinostoma ispp. 棘口吸蟲Gastrodiscoides hominis 人雙口吸蟲

Lung Flukes 肺吸蟲Paragonimus westermani 衛氏肺吸蟲

Blood Flukes 血吸蟲Schistosoma mansoni 曼森血吸蟲Schistosoma japonicum 日本血吸蟲Schistosoma haematobium 埃及血吸蟲Schistosoma mekongi 湄公血吸蟲Schistosoma intercalatum 間插血吸蟲

Liver Flukes 肝吸蟲Clonorchis sinensis 中華肝吸蟲Opisthorchis felineus 貓肝吸蟲Opisthorchis viverrini 泰國肝吸蟲Fasciola hepatica 牛羊肝吸蟲Dicrocoelium dentriticum 槍狀肝吸蟲

Trematodes 吸蟲

Other Flukes Eurytrema spp. 胰吸蟲

Some Worldwide Statistics on Trematoda*Crompton, D.W.T. 1999. How much human helminthiasis is there in the world? Journal of Parasitology 85(3): 397-403.

Clonorchis sinensisEchinostomes

Fasciola hepatica; F. gigantica

Fasciolopsis buskiHeterophyids

Opisthorchis viverrini, O. felineus

Paragonimus spp. Schistosomiasis

7 million 150,000

2.4 million

210,000900,000

10.3 million

20.7 million201 million

Disease / species Number of people infected worldwide

Number of yearly deaths worldwideunknown

unknown; few

unknown; few

unknown; fewunknown; few

unknown

unknown; fewperhaps 20,000

中華肝吸蟲

棘口吸蟲

牛羊肝吸蟲

薑片蟲

異形吸蟲

泰國/貓肝吸蟲

肺吸蟲

血吸蟲

Drugs Treatment of Hermaphroditic Trematodes

Praziquental

Bithional

Niclosamide

A halogenated diphenyl sulphide used for against trematode & cestode infections. It interfere the ATP production in the parasite

A chlorinated diphenyl derivatives.

A pyrazino-isoquinoline compound.Cause the worm to detach.