flat hermaphroditic worms Length- few millimeters to many

centimeters 70 species- colonize human intestine Fasciolopsis buski- most common other 3 trematodes— Heterophyes

heterophyes, Metagonimus yokogawai, and Echinostoma

Gastrodiscoides hominis, Phaneropsolus bonnei, and Prosthodendrium molenkampi – rarely cause human intestinal diseases

Intestinal flukes causes: Inflammation Ulceration mucous secretion at the site of attachment.Severe infections cause intestinal obstruction or malabsorption leading to hypoalbuminemia protein-losing enteropathy impaired vitamin B-12 absorption.

Stage Normal life cycle

1. Egg Expelled with bowel movement onto soil. Washed by rain into ponds.

2. Miracidia Hatches from egg in water. Has cilia, can swim vigorously and must find intermediate snail host in one to two hours or may be too exhausted to invade.

3. Redia Develop inside miracidia as little balls until expelled. Those are "mother" redia, and each one bears "daughter" redia for up to 8 months, all still inside the snail, and living on the fluids in the lymphatic spaces. Similarly, daughter redia are continually developing cercaria.

4. Cercaria Have a tail, use it to exit from snail and swim to a plant. If the snail is feeding on a plant, cercaria can latch onto plant with sucker mouth and start to encyst (form a "cocoon") within minutes. Tail breaks off and swims away to dissolve.

5. Metacercaria Two-walled cysts. The outer wall is very sticky. But as you eat the plant it is stuck to, the least pressure will break it, leaving the cyst in the mouth. The "almost unbreakable" inner cyst wall protects it from chewing, and the keratin-like coat prevents digestion by stomach juices. However when it reaches the duodenum, contact with intestinal juices dissolves away the cyst-wall and frees it. It then fastens itself to the intestinal lining and begins to develop into an adult.

6. Adult Lives in your intestine and can produce 1000 eggs per bowel movement and live many years.

Fluke Life-CyclesThe long and complex life-cycle of the fluke can be made easier to understand through the use of a mnemonic :Every - EggMirror - Miracidium (free-living in water)Spotted - Sporocyst (in snail)Red - Redia (in snail)Certainly - Cercaria (free-living in water/snail)Met - Metacercaria (in 2nd intermediate host)Approval - Adult

Kingdom: Animalia

Phylum: Platyhelminthes

Class: Trematoda

Family: Fasciolidae

Genus: Fasciolopsis

Species: buski

• a.k.a. giant intestinal fluke , small intestine

•Shape and size: large leaf-shaped worm, elongated and oval, 2- 7 cm long, size of an adult worm- 3 inches in length and 1 inch in width

• other characteristics: 1. fleshy body with ellipsoidal eggs

2. yellow brown in color

3. shell is transparent

4. blunt anterior end, undulating, unbranched ceca (sac-like cavity with a single opening)

5. tandem, dendritic testes, branched ovaries

6. ventral suckers to attach itself to the host

7. acetabulum is larger than the oral sucker with extensive vitelline follicles.

8. lack of cephalic cone or "shoulders" and the unbranched ceca unlike fasciolids

• mostly found in the continent of Asia like Bangladesh, Cambodia, China (in the central and southern regions), India, Indonesia, Laos, Malaysia, Pakistan, Taiwan, Thailand and Vietnam

• prevalence of up to 60% in India and mainland China and has an estimated 10 million human infections.

• Infections occur most often in school-age children or in impoverished areas with a lack of proper sanitation systems

•Animal reservoirs like pigs, rabbits and dogs and the use of untreated human feces for fertilizer make it difficult to prevent infection

•Acquired by ingestion of metacercariae on freshwater vegetation like water bamboo and water chestnut, water calthrop, water morning glory lotus and water hyacinth

• Other parts of the world, the giant intestinal fluke does not occur because the climate does not support its survival there or because the necessary intermediate hosts (plant or animal hosts that do not host the parasite during its sexually reproductive stage) are absent.

Timing: Prepatent period about 3 monthsEggs in water 3 - 7 wks for miracidiumCercaria produced at 30 - 50 daysMetacercariae live for at least a year if moist

•Fasciolopsiasis- disease

•light and asymptomatic

• In heavy infections : Abdominal pain, chronic diarrhea, anemia, ascites, toxemia , allergic responses, sensitization caused by the absorption of the worms allergenic metabolites (may cause death), and intestinal obstruction

•mucosal ulceration, GI hemorrhage, and/or abscess formation- erosion into the intestinal wall

•Absorption of toxic metabolites may lead to the development of, potentially fatal, systemic symptoms.

A. Mechanical injury, abdominal pain and intestinal disorder B. Spoliation of nourishment, covering the wall of intestine to affect

absorption C. Allergy caused by secretions and excrements D. Intestinal obstruction by a mass of the worms

A. Microscopic identification of eggs, or more rarely of the adult flukes, in the stool or vomitus is the basis of specific diagnosis Worms may be passed in feces or vomited.

B. Stool examination:

1.Direct fecal smear2.Water

sedimentation methodC. Fecal sedimentation of find large (67-

181 x 43 -95 micron) eggs with small, indistinct operculum.

D. Eggs identical to F. hepatica.

Avoiding the use of night soil as a fertilizer, and maintenance of proper sanitation and good hygiene. Additionally, snail control should be attempted.

Deworm definitive hosts - humans and pigs

Black Walnut Green Hull is proven effective against this trematode on his adult phase, for the larvae wormwood is known to help and the eggs cloves are used

Kingdom: AnimaliaPhylum: PlatyhelminthesClass: TrematodaOrder: EchinostomidaFamily: EchinostomatidaeGenus: Echinostoma

Species: ilonacum

Reddish gray, 2.5 – 6.5 mm by 1.0 – 1.35 mm Integument covered with plaquelike scales

Anterior end provided with a circumoral disk surrounded with a crown of 49 – 51 spines Oral sucker lies at the center of the disk Ventral sucker in the anterior fifth of the body Testes deeply lobed and in tandem Ovary located in front of the testes Uterus between the intestinal ceca bounded by the ventral sucker and ovary Crescent shaped vitelleria in the lateral fields of the posterior 2/3 of the body

The natural definitive hosts are humans The first intermediate snail host are Gyraulus

convexiusculus and Hippeutis umbilicalis The second intermediate hosts are the snails

Pila luzonica (“kuhol”) Rats may serve as an important reservoir host Infection is acquired by ingestion of raw snails

that serves as second intermediate hosts of the parasite

•Geographic distribution:●Infection is prevalent in Northern Luzon, Leyte, Samar and Mindanao.

●It is also found in Indonesia, India, China and Thailand.

Demonstration of eggs in the stoolsStraw colored, operculated,

ovoid, 83 – 116 by 58 – 69 u thin-shelled eggs

Immature when passed in the feces

Morphologically similar to eggs of Fasciola and Fasciolopsis