OS 213: Human Disease and Treatment 3(Circulation and Respiration)LAB 03: PARAGONIMUS WESTERMANI

Exam 1 | Parasitology Faculty | August 25, 2013

OUTLINEI. Life CycleII. OvumIII. Vectors

A. Primary: AntemelaniaB. Secondary: Sundathelphusa

IV. MetacercariaV. Adult

A. General FeaturesB. Reproductive

LIFE CYCLE

Figure 01. Life Cycle of Paragonimus westermani

OVUM Oval, yellowish-brown, thick-shelled Flat but prominent operculum (larger end) Abopercular portion is thickened (smaller end) Unembryonated at deposition Embryonates in water, moist soil or feces Develops into a miracidium within 2-7 weeks

Figure 02.Ovum

VECTORSPrimary: Antemelania

Figure 03. Antemelania

First intermediate host: the snails Antemelania asperata; Antemelania dactylus

Miracidium enters snailà sporocyst stage à redial stageà cercaria emerges à exit snail to infect 20 host

Cercariao Covered with spines and has an ellipsoidal body with small tail o Stylet present at dorsal side of the oral sucker

Secondary: Sundathelphusa Second intermediate host: mountain crab Sundathelpusa

philippina o Cercaria penetrates soft parts (gills, body muscles, viscera and

legs) and encysts into a metacercariao Crab may be infected by eating infected snails

Figure 04. Sundathelphusa

METACERCARIA Definitive host (man) acquires infection by eating raw or

insufficiently cooked crabs harboring metacercaria Metacercaria is round and measures from 381-457 micrometers After ingestion, metacercaria excysts in duodenum of host o Cysteine proteinases secreted by metacercaria’s excretory

bladder help in excystment and host immune modulation Adolescent worm then traverses through the intestinal wall, into

the peritoneal cavity, where it wanders about and embeds itself in the abdominal wall for several days

Afterwards, returns to coelom, migrates through diaphragm to pleural cavity where it develops into adulthood

Completion of development in the definitive host: 65-90 days Can persists in man up to 20 years or more Can also infect dogs, cats, rats

Figure 05. Metacecaria

Figure 06. Actual Metacercaria Specimen

Ronan | Kim | KevChan UPCM 2016 B: XVI, Walang Kapantay!

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OS 213: Human Disease and Treatment 3(Circulation and Respiration)LAB 03: PARAGONIMUS WESTERMANI

Exam 1 | Parasitology Faculty | August 25, 2013

ADULTGENERAL FEATURES

An adult may be as large as a coffee bean (7-12mm long, 4-6mm wide, and are 3.5-5mm thick)

Rounded anteriorly, slightly tapered posteriorly Vitellaria are branched extensively Found in pairs; threes in fibrotic capsules or cysts in host’s lungs Capsules have openings that allows eggs to escape; transported by

ciliary epithelium along with lung exudates

Figure 07.Adult

Figure 08. Paragonimus sp. Adult Lung Fluke.(Key: AC=acetabulum (ventral sucker); OV=ovary; CE=cecum; TE=testes; OS=oral sucker; UT=uterus; EB=excretory bladder)

Figure 09. Anterior end of Paragonimus sp.

Figure 10. Caudal part with caecum (slightly tapered end)

REPRODUCTIVE ORGANS Two testes are lobed, midway between ventral sucker Ovary located anterior to testes but posterior to ventral sucker Uterus is filled with eggs They are hermaphroditic

Figure 11.Uterus in focus (filled with eggs)

Figure 12. Male and Female Genitalia

Figure 13.Testes (Key: Paired lobulated pink structures)

Figure 14. Other Paragonimus structures(Key: orange arrow=cecum; blue arrow=uterus; violet

arrow=ovary; yellow arrow=testes; surrounding green=vitellaria)

END OF TRANSCRIPTION

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Ronan | Kim | KevChan UPCM 2016 B: XVI, Walang Kapantay!

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OS 213: Human Disease and Treatment 3(Circulation and Respiration)LAB 03: PARAGONIMUS WESTERMANI

Exam 1 | Parasitology Faculty | August 25, 2013

Ronan | Kim | KevChan UPCM 2016 B: XVI, Walang Kapantay!

3of 3