in vitro culture and isoenzyme analysis of giardia lamblia

vaccines and chemotherapeutic agents. Control will also depend to a great extent
on education of children and adults about hygiene and sanitation. Equally
essential is the need to resolve the present taxonomic confusion in order to
facilitate effective epidemiological control when accuracy in species and strain
definition has been achieved. The extent of interspecies transmission (in order to
elucidate the role played by animals in transmission of giardiasis to humans) also
requires thorough investigation. These remarks emphasise the crucial need to fully
understand the pathogenesis/virulence factors of these organisms.
Finally, several studies have revealed marked genetic diversity among isolates.
Some of these studies illustrate that variability exists in many aspects of Giardia
infection, such as drug susceptibility, infectivity patterns, susceptibility to
enzymatic lysis and antigenicity. In view of the fact that many cell-cell interactions
occur at the surface (including host-parasite interactions), it remains to be shown
whether the surface antigenic variations have any association with virulence
determinants during the natural course of infections in vivo.
1.9 Study objective
Evidently, giardiasis still remains a poorly understood gastrointestinal infection.
Furthermore, Giardia is not a fully defined organism at present. The environment,
host factors and the parasite cyst interact to propagate giardiasis. A thorough
understanding of the organism requires more in-depth knowledge of its biology
and biochemistry. Epidemiological intervention to break the life-cycle, preventive
control measures and identification of prospective drug target sites and vaccine
design would be facilitated by a more comprehensive knowledge of the parasite.
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