AL AZHAR UNIVERSITY Lecture Notes on Parasitology 2024-2025 PDF

AL AZHAR UNIVERSITY Faculty of Medicine for Girls Year 1 -Semester 1 Module Name: Biomedical science Course code: IMP-07-10105 Credit hours: 4 crh Academic year: 2024 / 2025 Lecture:1 Parasitology Department Introduction to parasitology Prof.Dr. Attiat Abd El Hameed...

AL AZHAR UNIVERSITY Faculty of Medicine for Girls Year 1 -Semester 1 Module Name: Biomedical science Course code: IMP-07-10105 Credit hours: 4 crh Academic year: 2024 / 2025 Lecture:1 Parasitology Department Introduction to parasitology Prof.Dr. Attiat Abd El Hameed [email protected]  Intended Learning Outcomes (ILOS) At the end of the lecture the student should be able to : Define the meaning of Medical Parasitology Define the meaning of parasite and host Recognize Host parasite relationship Define the meaning of zoonotic parasitic disease Define the meaning of Vector Recognize classification of the parasites know how to name and write the parasites Classify Medical Parasitology  INTRODUCTION to MEDICAL PARASITOLOGY Medical Parasitol ogy A science that deals with parasites which cause human diseases History ‫بردية ايبرس‬ The first written record of a certain parasitic infection come from a period of Egyptian Medicine from 3000 to 400 BC particularly the Ebers papyrus of 1500 BC discovered at Thebes (Luxor) It is currently kept at the library of Leipzig in Germany. Parasite Is the organism which lives at the expense of another organism (host ) taking its food or food & shelter and may cause harm to the host  Host parasite relationship Their relation will be one of the following types: 1. Parasitism: One organism live at the expense of the other, the later usually suffers from the association. 2. Symbiosis: two different organisms living together, so dependent on each other, non of them suffers any harm. 3. Commensalism: When the parasite benefited from the host while the host neither benefited nor harmed. Parasites can be Classified: I. According to their habitat: 1. Ectoparasites: parasites living on or affecting the skin surface of the host, e.g. bugs, etc. 2. Endoparasites: Parasites living within the body of the host. e.g. Ascaris lumbricoides, etc. II. According to their dependence on the host 1. Obligate (Permanent) parasites: Parasite depends completely upon its host. This parasite can not live outside its host. e.g. Lice. 2. Facultative (Temporary) parasite: Parasite only visit the host from time to time for meals, e.g. Ticks. 3- Coprozoic parasite: Parasites contaminate fecal samples without infecting the host, e.g. free living form of amoebae & flagellates. 4- Spurious parasite: Parasitic stage ingested in food and passed without change in stool and miss diagnosed as infected case, e.g.Fasciola & Capillaria hepatica ova in raw liver of infected animals. III. According to their Pathogenicity: 1. Pathogenic parasites: It causes disease in the host, e.g. Entamoeba histolytica 2. Commensal (Non-Pathogenic ) parasite: The parasite derives food and protection from the host without causing harm, e.g. Entamoeba coli 3. Opportunistic parasites: a-Parasites which cause mild disease in immunologically healthy individuals, but they cause severe disease in immuno-suppressed hosts, e.g. Toxoplasma gondii. b-Free living parasite can infect man, e.g. Acanthamoeba  Types of parasites Ectoparasites Permanent Endoparasites parasites Temporary parasites Coprozoic parasites Laboratory Incidental masking Opportunistic parasites parasites parasites Spurious parasites  Host Host is an organism which harbors the parasite.  Types of Hosts 1. Definitive or final host (D.H): it is a host harbors the adult or sexually mature stages of a parasite & fertilization takes place in it, e.g. Man in case of Schistosoma. Female Anopheles in case of malaria. 2. Intermediate host: Is a host harboring sexually immature or larval stage of a parasite and in which no fertilization takes place in it e.g. * Snails in case of Schistosoma * Man in case of malaria. 3. Reservoir host: An animal that harbors a parasite as the human and acts as source of infection to humans, e.g.* Cats in case of Heterophyes heterophyes. 4. Carrier host: A host harboring and disseminating a parasite but exhibiting no clinical sign e.g., Man in case of Entamoeba histolytica. 5. Accidental (Incidental) host: Infection of a host other than the normal host species. A parasite may or may not continue full development in this host e.g., *Man in case of accidental myiasis.  Vector Any arthropod or other living carrier which transports a pathogenic organisms from one host to another. A- With Biological changes: Vectors that complete the life cycle of the parasite, e.g. *Culex that transmit wuchereria bancrofti etc.. B- Without biological changes: They are passive carriers of parasites, not essential in the life cycle. *Mechanical House fly transmit E.histolytica *Transport (Paratenic) (e.g. Small fish transmit Diphylobothrium latum larva).  Types of Hosts Adult stage Larval stage Definitive Intermediate host host (D.H) (I.H) Vector Reservoir host (R.H) Transport host (paratenic)  Zoonotic diseases are infectious diseases of animals (usually vertebrates) that can naturally transmitted to man.  Prevention and Parasite name control Diseases Treatment Objectives of Geographical distribution parasitology Diagnosis Epidemiology Clinical picture Morphology Pathogenesis Life cycle  Taxonomy (Nomenclature) of parasites Animal Kingdom Phylum Class Order Family Genus Species Every parasite is known to have two names: *Genus and Species of the parasite, must be underlined or written in italic letters. *Genus starting with capital letter. *Species starting with small letter. Ascaris lumbricoides or Ascaris lumbricoides.  Parasites Worm Protozoan Arthropod Protozoology Helminthology Entomology Medical Parasitology Classification I- Multicellular parasites: 1) Medical Helminthology 2) Medical Entomology II- Unicellular: 1) Medical Protozoology MCQ Which of the following is the host that harbors the larval stage of the parasite? a-Reservoir host b-Definitive host c-Intermediate host d- Final host  -Which of the following are unicellular parasites? a-Protozoa b-Helminthes c-Arthropods d-Both helminthes and arthropods I-Define: Commensalisms. Opportunistic parasites.  References - -Medical parasitology,Ruth Leventhal,Russell F.Cheadle.Publisher: F.A.Davis Company,2012;6 th edition (2012). -Human Parasitology book of Parasitology Department. Thank you and good luck