Echinococcosis |
Echinococcosis
is an important medical, veterinary and economic concern in
India. The public health and economic significance of echinococcosis
as the most important of the cestode zoonoses, have resulted,
particularly in the case of E. granulosus, in the widespread
global perpetuation of Echinococcus in a variety of domestic,
man-made life-cycle patterns (Eckert 1998; Schantz et al. 1995).
Although the disease in domestic animals is usually asymptomatic
and detected only at the time of post mortem inspection at the
abattoir, it causes great economic loss through condemnation
of infected offal, in particular liver. Surveys of prevalence
of echinococcosis in livestock are important for comparing transmission
levels quantitatively within and between regions, and for determining
the significance of each species of animal in the transmission
dynamics.
The recognition
of strain variation is a major pre-requisite for strategic
control efforts aimed at limiting transmission in an endemic
area. A number of intraspecific variants or strains are known
to occur within the species E. granulosus (Eckert and Thompson
1995). Variation in the pathogenicity of strains/species of
Echinococcus will influence the prognosis in patients with
echinococcosis. Gordo and Bandera (1997) demonstrated that
morphological characteristics can also be used as a valid
criterion for strain identification. Despite the strong evidence
to show the endemicity of these serious zoonoses, documentation
and surveillance data concerning to the prevalence and risk
factors associated with zoonotic parasites in India is largely
lacking. There is an urgent need for more recent parasite
data to be obtained. In Indian scenario, the conditions for
the establishment and transmission of hydatidosis in both
livestock and humans are very ideal. The purpose of this study
was to document the prevalence and to analyze morphological
characteristics from hydatid cysts to test their suitability
for strain identification. Hydatid
disease or Echinococcosis is a zoonotic disease caused by
the larvae (metacestode) of the cestode species of the genus
Echinococcus like E. granulosus, E. multilocularis, E. vogeli
or E. oligarthus. Classical Cystic Echinococcosis (CE) is
caused by E. granulosus complex, while E. multilocularis and
E. vogeli are responsible for alveolar echinococcosis and
polycystic echinococcosis, respectively. The study of E. granulosus
species has revealed identification of substantial phenotypic
and genetic variability and several strains. All identified
strains utilize dogs and other canids as definitive hosts,
but differ in the choice of intermediate host, geographic
distribution, adult and metacestode morphology, maturation
time in definitive hosts, organ localization of metacestode,
and protoscolex production. At least, seven of nine E. granulosus
genotypes are infective to humans. Globally, most human cases
of CE are caused by the sheep strain (G1) of E. Granulosus.
In India G1 and G5 (cattle strain) strain of E. granulosus
have been frequently associated with CE. G2 genotype (Tasmanian
sheep strain) in buffalo has been reported from India. Humans
acquire primary CE by ingestion of E. granulosus eggs excreted
by infected carnivores. The infection may be acquired by contact
with infected definitive hosts, egg-containing feces, or egg-contaminated
plants or soil followed by direct hand-to-mouth transfer.
Dog ownership has not been found to be a risk factor in seropositive
individuals, indicating an indirect contact with dog feces
in the environment. Eggs can also be ingested with vegetables,
salads, uncooked fruits, drinking water, and other plants
that become contaminated. Key facts
Human echinococcosis is a zoonotic disease (a disease that is transmitted to humans from animals) that is caused by parasites, namely tapeworms of the genus Echinococcus. Echinococcosis occurs in 4 forms:
The two most important forms, which are of medical and public health relevance in humans, are cystic echinococcosis (CE) and alveolar echinococcosis (AE). Video links Echinococcosis
Documentry Echinococcosis Echinococcosis is a parasitic disease of tapeworms of the Echinococcus
type. The two main types of the disease are cystic echinococcosis
and alveolar echinococcosis.[1] Less common forms include polycystic
echinococcosis and unicystic echinococcosis.
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