Abstract
Protozoan and metazoan parasites can be identified by a wide range of techniques, from light microscopy, through electron microscopy to
molecular characterization. In many cases, preserved infected host tissue processed for histopathology is the only parasite material that is available. This is
particularly the case if experienced parasitologists are not involved in sample collection or if specialized facilities are not available for timely sample
processing.
Examination of parasites in tissue sections is fascinating and has several advantages, including recognition of the host-parasite
relationship, and visualization of internal structures of the parasites. However, a section typically provides only 5 um thick slices through the parasite, thus
multiple sections need to be examined to gain a perspective of the whole organism, and some features can never be resolved adequately in tissue section. Similar
to the commonly used diagnostic keys for identification of whole parasites, diagnostic criteria are available for identification of parasites in tissue section
1-6, and a variety of special stains can be used to enhance visualization of certain features.
The workshop will provide practical guidance on the preparation and interpretation of protozoan and metazoan parasites in tissue sections, and
will be illustrated with numerous examples of infections in aquatic hosts, including cephalopods, fish and marine mammals.
References
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6. Murche