Question

a group of multicellular parasitic organisms that exhibit microscopic infective and diagnostic stabes on their lifestyle

Answer 1

An organism that lives inside the host of another organism for food and shelter is termed as parasite.

Classification

Parasites can be classified as Endoparasites (living inside host) and Ectoparasites (living outside host)

Endoparasites

Endoparasites are commonly classified as,

Protozoa – These are single celled and microscopic organisms. The organisms may be parasitic or free living.

The protozoa are sub classified as,

§ Sarcodina - Eg: Entamoeba

§ Mastigophora - Eg: Leishmania

§ Ciliophora - Eg: Balantidium

§ Sporozoa - Eg: Plasmodium

Helminths – These are multicelled and large organisms. The larvae are microscopic whereas the adult stages are macroscopic. The organisms may be parasitic or free living.

The helminths are sub classified into,

§ Platyhelminths - Eg: tapeworm

§ Acanthocephalins - Eg: Spiny head worms

§ Nematodes - Eg: Round worm

Ectoparasites

These organisms are usually arthropods that suck blood. Examples are mosquitoes, lice, and ticks. Some are vectors transmitting the disease between several hosts.

Diagnosis of parasites

Parasitic infections commonly occur in tropical and subtropical climates. It mainly affects rural regions and low income countries. Young children are more prone to parasitic infections than elders. People living in poorly sanitized and less hygiene regions are more prone to such infections.

Diagnostic methods of a parasitic infection can be done using microscopy and other laboratory techniques. Common samples collected are blood, and fecal specimens.

For microscopic detection,

§ Blood samples are collected for parasites such as Plasmodium and Leishmania.

§ Similarly, for helminthes such as tape worm the fecal sample is collected as these parasites live in the enteric region of the host.

Other diagnostic methods,

§ Culturing of samples for infections produced by Entamoeba can be diagnosed.

§ Immunodetection for infections such as for Trichinosis.