Fasciolopsis buski - Classification, Morphology, Manifestation, Transmission

Introduction of Fasciolopsis buski

Fasciolopsis buski is the causative agent of fasciolopsiasis in humans. It is also known as the giant intestinal fluke as it is an exceptionally large parasitic fluke – the largest parasite known to infect humans. It also has veterinary importance as it can also cause infection in pigs.

Also, Fasciolopsis buski is the most common human intestinal trematode causing infection in man.

Classification of Fasciolopsis buski

Kingdom: Animalia

Phylum: Platyhelminthes

Class: Trematoda

Order: Plagiorchiida

Family: Fasciolidae

Genus: Fasciolopsis

Species: F. buski

Habitat of Fasciolopsis buski

The habitat of Fasciolopsis buski is the duodenum and jejunum of pigs and humans where it remains attached to the mucosa.

Morphology of Fasciolopsis buski

The important morphological forms of Fasciolopsis buski include:

• Adult worm

• Egg

• Metacercariae

Adult Worm

• adult Fasciolopsis buski measures 2cm to 7.5cm in length, 8mm to 20mm in breadth, and 0.5mm to 3mm thick

• the body is elongated and fleshy with a broadly rounded posterior end

• two suckers are present- oral sucker and ventral sucker

• large ventral sucker measuring 3mm lies close to 0.5mm oral sucker

• this morphological form of Fasciolopsis buski resembles Fasciola hepatica but Fasciolopsis buski lacks a cephalic cone, intestinal caeca, and lateral branches

• lifespan is around 6 months which is short

Egg

• eggs of Fasciolopsis buski are large - 130μm to 140μm x 80μm to 85μm

• are bile stained and operculated

• each adult worm produces 8,000 to 50,000 eggs per day

• identical to that of Fasciola hepatica

Infective form

Metacercariae

• metacercariae of Fasciolopsis buski is infective to both man and pig

• harbors in the freshwater plants

Epidemiology of Fasciolopsis buski

Epidemiology studies for Fasciolopsis buski have confirmed that they occur in China, Taiwan, Thailand, Bangladesh, India, and Indonesia.

Reservoir, Source of Fasciolopsis buski

The main source of Fasciolopsis buski infection is the second intermediate host – such as water caltrops (Trapa bispinosa), water hyacinth (Eichlornia), water chestnut (Eleocharis tuberosa), lotus (Nelumbium), water bamboo (Zizania aquatica) harbor the infective stage (metacercariae)

In most of the world, Pig is the major reservoir host.

Transmission of Fasciolopsis buski

The transmission of Fasciolopsis buski occurs via the following routes:

• drinking water contaminated with metacercariae

• consumption of aquatic plants raw which is harboring metacercariae – including water caltrops (Trapa bispinosa), water hyacinth (Eichlornia), water chestnut (Eleocharis tuberosa), lotus (Nelumbium), water bamboo (Zizania aquatica)

• peeling off with teeth or biting aquatic plants harboring metacercariae

Clinical manifestations of Fasciolopsis buski

Fasciolopsiasis, which clinically manifests as intestinal infection, is caused by Fasciolopsis buski. Although symptoms are absent in most cases, heavy infections do present some syndromes.

Such syndromes include nausea, severe anemia, diarrhea, and epigastric pain.

Complications of Fasciolopsis buski

During the late stage of the disease, asthenia with ascites and anemia may occur.

Prognosis of Fasciolopsis buski

With treatment and supportive therapy, the prognosis of Fasciolopsis buski is very good.