9.1 PARASITES

Taxonomy and classification of parasites.

Parasites are organisms that live on or in a host organism and derive their nutrients at the host's expense. Parasites can cause diseases in humans. Some are microscopic, like protozoa and viruses, while others are much larger, like worms.

The classification of parasites is broad and involves multiple taxonomic groups. Here's a basic overview of the taxonomy and classification of parasites:

Protozoa (Single celled Eukaryotes)+ Helminths (Multicellular worms) + Ectoparasites+ Others 

1. Protozoa (Single-celled Eukaryotes)

  • These are single-celled microscopic organisms that are eukaryotic in nature, meaning they have a nucleus and other cellular organelles.

  • Main Classes & Examples:

  • Amoebae+ Flagellates+ Ciliates+ Sporozoans 

    • Amoebae: e.g., Entamoeba histolytica (causes amoebic dysentery)

    • Flagellates: e.g., Trypanosoma brucei (causes African sleeping sickness), Giardia lamblia (causes giardiasis)

    • Ciliates: e.g., Balantidium coli (the only ciliate to infect humans, causing balantidiasis)

    • Sporozoans: e.g., Plasmodium spp. (causes malaria)

2. Helminths (Multicellular worms)

These are macroscopic, multicellular organisms. They can be classified into:

Nematodes (Roundworms) + Trematodes(Flukes)

Nematodes (Roundworms)

  • Ascaris lumbricoides (causes ascariasis)

  • Enterobius vermicularis (causes pinworm infection)

  • Necator americanus and Ancylostoma duodenale (hookworms)

  • Cestodes (Tapeworms)

  • Taenia saginata (beef tapeworm) and Taenia solium (pork tapeworm)

  • Echinococcus granulosus (causes cystic echinococcosis)

Trematodes (Flukes)

  • Schistosoma spp. (causes schistosomiasis or bilharzia)

Clonorchis sinensis (liver fluke)

3. Ectoparasites

These organisms live on the surface of their host.

Anthropods+ Mollusks 

  • Arthropods: e.g., lice (Pediculus humanus), fleas, ticks, and mites.

  • Mollusks: Some snails act as intermediate hosts for flukes such as schistosomes.

4. Others

  • Pentastomids: Tongue worms that typically infect reptiles but can be found in humans.

Taxonomy and Classification of Parasites

Parasites are organisms that live on or in a host organism and derive their nutrients at the host's expense. They can cause diseases in humans. Parasites can be classified into different taxonomic groups. Here's an overview:

Protozoa (Single-celled Eukaryotes)

  • These are single-celled microscopic organisms that are eukaryotic in nature, meaning they have a nucleus and other cellular organelles.

  • Amoebae

    • Entamoeba histolytica (causes amoebic dysentery)

  • Flagellates

    • Trypanosoma brucei (causes African sleeping sickness)

    • Giardia lamblia (causes giardiasis)

  • Ciliates

    • Balantidium coli (causes balantidiasis)

  • Sporozoans

    • Plasmodium spp. (causes malaria)

Helminths (Multicellular worms)

These are macroscopic, multicellular organisms. They can be classified into:

  • Nematodes (Roundworms)

    • Ascaris lumbricoides (causes ascariasis)

    • Enterobius vermicularis (causes pinworm infection)

    • Necator americanus and Ancylostoma duodenale (hookworms)

  • Cestodes (Tapeworms)

    • Taenia saginata (beef tapeworm)

    • Taenia solium (pork tapeworm)

    • Echinococcus granulosus (causes cystic echinococcosis)

  • Trematodes (Flukes)

    • Schistosoma spp. (causes schistosomiasis)

    • Clonorchis sinensis (liver fluke)

Ectoparasites

These organisms live on the surface of their host.

  • Arthropods

    • Lice (Pediculus humanus)

    • Fleas

    • Ticks

    • Mites

  • Mollusks

    • Snails (act as intermediate hosts for flukes)

Others

  • Pentastomids (Tongue worms, typically infect reptiles but can be found in humans)

This mind map provides a basic overview of the taxonomy and classification of parasites, including protozoa, helminths, ectoparasites, and other parasites.

This is just a basic overview of the taxonomy and classification of parasites. Each category has numerous subcategories and individual species with unique characteristics and pathogenic mechanisms.