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Parasitology Historical groupings

Ecto/Endoparasites

Obligate/Facultative parasites

Permanent/Temporary parasites

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Biological Vectors Hyperparasitism

– e.g mosquito carrying malaria protozoan

Biological vectors

Mechanical vectors

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Host–Parasite Relationships

Definitive host

Intermediate host

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Parasite Defenses

Encystment

Immunological challenges

Host cell invasion to escape Immune system

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Parasite Damage

Nutritional deprivation

Direct trauma/obstruction

Inflammation

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Plant-like Protozoa

(Algae)– Euglenoids

– Diatoms

– Dinoflagellates

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Fungus-like Protozoa Water molds

Slime Molds

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Animal-like Protozoa Mastigophorans

– Use flagellae• Trypanosoma

brucei

• Trypanosoma cruzi

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Animal-like Protozoa

Amebozoa– Ameboid movement with

pseudopods• Entamoeba histolytica

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Animal-like Protozoa Apicomplexans Apical enzyme

complex assists host cell penetration– Plasmodium

– Toxoplasma gondii

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Animal-like Protozoa

Ciliates– Move with cilia– Balantidium coli

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Fungi Mycology Single celled

Multicellular

– Thallus– Mycelium– Hyphus– Septae

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Importance of Fungi Industry

Decomposers

Antibiotic producers

Pathogens

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Classification — Fungal Phyla

Phylum Zygomycota Conjugation Fungi

– Coenocytic hyphae

– Molds

– Rhizopus

– Opportunistic

Phylum Ascomycota (Sac) Yeasts and multicellular

fungi Septate hyphae when

multicellular– Penicillium

– Saccharomyces

– Candida

– Trichphyton

– Aspergillus

– Blastomyces

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Classification — Other Phyla

Basidiomycota (Club)– Multicellular, septate hyphae

Deuteromycota (Imperfect)– Sexual forms not (yet?) observed– Likely to be Ascomycota when classification is

completed

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Helminths - Platyhelminths

Phylum Platyhelmintha (Flatworms)

Flukes (Class = =Trematodes)– Schistosoma japonicum

Tapeworm (Class = Cestodes)– Taenia saginata

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Helminths - Nematodes

Phylum Nematoda (Roundworms)– Trichinella spiralis

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Arthropods

Arachnids– Spiders, scorpions,

ticks and mites– Ticks as Vectors

• Ixodes for B. burgdorferi

• Viral encephalitis• Colorado tickfever• Bacterial Rocky

Mountain spotted fever

Insects– Vectors for Borrelia

causing relapsing fever– Fleas can carry

Yersinia pestis– Mosquitoes carry

Plasmodium and Wuchereria

Crustaceans– Few may transmit

disease, including Guinea worms