Faculty of Allied Medical Science Parasitology ( MLPR-201) fall 2013

1. Faculty of Allied Medical ScienceParasitology(MLPR-201)fall 2013

2. Introduction to Parasitology Prof.Dr. Hamdy El-Wakil Professor in Parasitology. Vice Dean in faculty of physiotherapy pharos University 2013M-1434H

3. Parasitology • Human parasitology is the study of those organisms which parasitize humans. According to the very broad definition of parasitology, parasites should include the viruses, bacteria, fungi, protozoa (protista) and metazoa (multi-celled organisms) which infect their host species.  However, for historical reasons the first three have been incorporated into the discipline of Microbiology. 

4. Learning Outcomes After completing this course, you should be able to: • Discuss how important parasites can be classified according to kingdom and phylum • State the meaning of commonly-used terms • Describe how parasitic infections affect communities in poor countries and that knowledge of their life cycle is necessary for effective prevention and control • Discuss the epidemiology, basic life cycle, clinical presentation, management and control of some important parasitic infections Note: This course will contain many unfamiliar terms. You are NOT expected to remember the classifications and names of all of the different parasite species. The emphasis is on understanding basic concepts and being able to illustrate these with some important examples. After completing this course, you will associated a quiz to assess your learning.

5. The burden of some major parasitic infections

6. Classification of parasites and vectors Animal Kingdom Sub-Kingdom (Metazoa) Multicellular animals Sub-Kingdom (Protozoa) Unicellular parasites=kingdom Protista Phylum Helminthes : Phylum Arthropods :Phylum Molluscs Subphylum: Sarcodina e.g. Amoeba Phylum: Sarcomastigophora: Subphylum:Mastigophora e.g. Trypansoma Phylum: Ciliphora: Class: Ciliates e.g. Balantidium coli Phylum: Apicomplexa: Class: Sporozoa e.g. Plasmodium Sp.

7. Taxonomic classification of parasitic organisms Animal Kingdom

8. Taxonomic classification of Helminths

9. Epidemiology • Although parasitic infections occur globally, the majority occur in tropical regions, where there is poverty, poor sanitation and personal hygiene • Often entire communities may be infected with multiple, different organisms which remain untreated because treatment is neither accessible nor affordable • Effective prevention and control requires "mass intervention strategies” and intense community education. Examples include: • General improved sanitation: pit latrines, fresh water wells, piped water • Vector control: insecticide impregnated bed nets, spraying of houses with residual insecticides, drainage, landfill • Mass screening and drug administration programmes which may need to be repeated at regular intervals

10. Parasite transmission Direct (without intermediate host) Indirect (with intermediate hosts) • (1) Requiring Two • intermediate hosts • H. Hetrophyes • Clonorchis sp. • Fasciolopsisbuski • Paragonimuswestermani • Diphyllobothrium L. • (2) Requiring one • intermediate host Wuchereria bancrofti Onchocerca volvulus Loa loa Dracunculus medinensis Dipylidium caninum Taenia spp .Schistoma spp .Leishmania spp. • Fasciola spp. • (2) Immediately • infective • Entamoeba histolytica • Giardia lamblia Balantidium coli Trichomonas sp .Hymenolepis nana Enterobius vermicularis Sarcoptes scabiei Pediculus huminus Phthirus pubis • (1)Taking a period to become infectious • Ascaris lumbricoides  Trichuris trichiura  Ancylostoma duodenale  Necator americana Strongyloidesstercoralis

11. Definitions: What is ….? • Eukaryote: a cell with a well-defined chromosome in a membrane-bound nucleus. All parasitic organisms are eukaryotes • Prokaryotic organelles • Prokaryotes are not as structurally complex as eukaryotes, and were once thought not to have any internal structures enclosed by lipid membranes. • Protozoa: unicellular organisms, e.g. Plasmodium (malaria) • Metazoa: Multicellular organisms, e.g. helminths (worms) and arthropods (ticks, lice) • An endoparasite: “a parasite that lives within another living organism” – e.g. malaria, Giardia • An ectoparasite: “a parasite that lives on the external surface of another living organism” – e.g. lice, ticks

12. Definitions: What is ….? • Definitive host: “the organism in which the adult or sexually mature stage of the parasite lives” • Intermediate host: “the organism in which the parasite lives during a period of its development only” • Zoonosis: “a parasitic disease in which an animal is normally the host - but which also infects man” • Vector: “a living carrier (e.g.an arthropod) that transports a pathogenic organism from an infected to a non-infected host”. A typical example is the female Anopheles mosquito that transmits malaria

13. Definitions: What is ….? Parasitology : Is the science which deals with parasitism, in other hand, it studies the host parasite relationships. Medical parasitology:Deals with the study of parasites of animal origin, belonging to the animal kingdom, and affecting man, the disease they produce, the various methods of their diagnosis, their treatment and finally prevention and control. Parasite : Any organism is considered as a parasite when it lives either on or in another organism to obtain food and shelter without compensation.

14. Host : Is the living organism which harbours the parasites. Habitat : Is the site in the host where the parasite lives. Parasites vary according to their biological habits. Definitions: What is ….? Commensal : If the parasite derives benefit from its host without harming it, it becomes, known as a commensal. Symbiosis: If on the other hand the association between them is so that one cannot live without the help of the other, then this relationship becomes known as symbiosis, but usually a parasite causes injury to its host.

15. Maintains a relatively moderate steady level of parasitism in man in a certain area. Also, a parasite is called hyperendemic when its prevalence or incidence is relatively high. Epidemic parasite: When these exist a sharp rise in the prevalence of infection or infestation culminating in an intense outbreak of the disease. Endemic parasite:

16. Assignments • Students will prepare an assignment in one of the parasites that have been taken in your lecture. Three points should be covered in his/her assignment: • A real infective stage photo of the parasite. • Diagnostic stage photo • Parasite scientific name, illness or the disease name ,Importance and life cycle.