ECHINOCOCCUS
(GRANULOSUS AND
MULTILOCULARIS)
ABDI RAHMAN
GULAID
INTRODUCTION
Echinococcosis:
Echinococcosis commomly known as
Hydatid Disease or Hydatidosis, is
caused by a parasitic cestodes
(tapeworms)
of
the
genus
Echinococcus.
 Four species of Echinococcus cause infection in
humans are:
E. granulosus causes cystic echinococcosis
E. multilocularis causes alveolar echinococcosis
E. vogeli causes polycystic echinococcosis
E. oligarthrus is an extremely rare cause of
human echinococcosis.
THE GEOGRAPHIC
DISTRIBUTION
Echinococcus granulosus is widely distributed across Canada and
more frequent in rural, grazing areas.
Echinococcus multilocularis occurs in the northern hemisphere,
including central Europe and the northern parts of Europe, Asia, and
North America.
E. vogeli and E. oligarthrus occur in Central and South America.
E.GRANULOSUS HOST
& E.MULTILOCULARIS HOST
Size
E. granulosus
Usually 3 to 6 mm
long and consist of a
scolex with suckers
and hooks, as well
as at least three
proglottid segments.
Definitive
Adult worm: (adult
worm): wolves,
coyotes, domestic
dogs
E. Multilocularis 1.2-3.7 mm long
Adult worm: Arctic
with two to six
and red foxes,
proglottic segments. coyotes, sometimes
domestic dogs and
cats.
Intermediate
Larval worm:
Sheep, Goat, Camel, cattle,
Goat, and Horse .
Larval worm: rodents
(voles, mice, muskrats).
Humans
TRANSMISSION AND LIFE CYCLE OF
ECHINOCOCCUS
The Hydatid Tapeworm Life Cycle Diagram
1.
2.
3.
4.
5.
6.
Adult worm present in intestine of definitive host
Eggs passed in feces, ingested by humans or
intermediate host
Onchosphere penetrates intestinal wall, carried via
blood vessels to lodge in organs
hydatid cysts develop in liver, lungs, brain, heart
After ingestion, the protoscolices attach to the
intestine.
Ingested protoscolices attach to small intestine and
develops into adult worm and the cycle starts all over
again.
LIFECYCLE:
ECHINOCOCCUS EGG IN FECES
SYMPTOMS
• E. granulosus
• Can remain silent for years
• It is the enlarging cysts that cause symptoms in organs
• Hepatic involvement (75%) (abdominal pain, mass in the
hepatic area, biliary duct obstruction)
• Pulmonary involvement (chest pain, Cough, hemoptysis)
• Brain, bone, and heart (10-20%)
• Rupture of cyst (fever, hives, pus, anaphylactic shock, and the
cyst spreads throughout body cavity)
• E. multilocularis
• Affects the liver as a slow growing destructive tumor
• Abdominal pain, biliary obstruction, and sometimes metastatic
lesions in lungs and brain are common symptoms
A SECTION OF HUMAN LUNG SHOWS
MULTIPLE PROTOSCOLECES LIBERATED
FROM A RUPTURED HYDATID CYST
E. MULTILOCULARIS
SIGNS AND SYMPTOMS OF ALVEOLAR HYDATID
DISEASE
No early symptoms
Cysts in multiple body organs
Symptoms of liver infestation: upper abdominal
pain , weakness , weight loss , chest pain , cough,
coughing blood , jaundice
Symptoms of brain infestation:
 Blindness
 Epilepsy
Symptoms of ruptured cysts:
 Allergic rash
 Fever
DIAGNOSIS
• Imaging (CT, MRI, and ultrasound)
• Serologic testing (enzyme immunoassay,
immunofluorescent assay)
• Examination of cyst fluid
Protoscoleces in a hydatid cyst
removed from lung tissue
TREATMENT
Surgical removal via laparoscopy, can be
curative for the treatment of echinococcosis
Medication is sometimes effective to keep
the cyst from growing back
 Praziquantel for definitive host (dog)
 Albendazole, mebendazole
intermediate host (sheep, other host)
REMOVAL BY SURGERY
CONTROL METHOD
• interrupt lifecycle by an possible means.
• Destroy stray dogs
• General education program
• Sheep herders should not live closely with their
dogs
SOURCES
 - Center of Disease Control.
http://www.dpd.cdc.gov/dpdx/html/Echinococcosis.htm
journals.cambridge.org/production/action/cjoGetFulltext?fulltex
td... by JD SMYTH - 1964 - Cited by 64 - Related articles
 - www.sciencedirect.com/science/article/pii/0166685185900167
by DP McManus - 1985 - Cited by 42 - Related articles
 - www.springerlink.com/index/MD4LQW968V6TUBPE.pdf by
CP Nunes - 2004 - Cited by 12 - Related articles
 http://www.fao.org/docrep/t1300t/t1300T0m.htm by A. Permin
and J.W. Hansen