General Parasitology Introduction Parasitology Department General Parasitology Introduction By Hala Elwakil, MD halawakil39@gmail.com

Teaching and learning methods 1- lectures 2- Practical sessions Video clip Prelab presentation Prelab assessment Formative exam Microscopic slides demonstration Small group discussion 3- POS Self directed learning halawakil39@gmail.com

Student Assessment 6.2 Time of Assessment: Continuous assessment: Methods Used: 6.2 Time of Assessment: Continuous assessment: Block exams   POS Activity copy book ( attendance , drawing ) Integrated case studies Quizzes Practical exam 4 block exams at the end of each block 10 sessions IN 2nd block; W14,15,16 3rd block; W2,3,4,5 4th block; W10,11,12 In the practical sessions all the year 3 Integrated sessions after first, second and third blocks 3 quizzes 2nd block; W15) 3rd block; W4) 4TH block; W12) Week 16 halawakil39@gmail.com

All over the academic year in the practical sessions Final year Written MCQs Essay Problem solving Practical OSCE   Final exam Formative exams All over the academic year in the practical sessions halawakil39@gmail.com

Learning resources Lecture notes by staff of Parasitology department   Essential Books (Text Books) Paniker’s Textbook of Medical Parasitology Markell & Voge’s Textbook of Medical Parasitology Recommended Books Medical Parasitology. A Self Instructional Text, 6th edition by Leventhal and Cheadle Web Sites, Faculty official website -http://telemed.shams.edu.eg/moodle3/course/view.php?id=8 the photographed parasitic stages on microscopic slides uploaded on faculty web site https://1drv.ms/f/s!ApoO_TmSvm1Vhhjpk0nVt6YlltNH halawakil39@gmail.com

Intended Learning Outcomes By the end of this lecture , the student will be able to: Differentiate between types of hosts Differentiate between types of parasites Classify the parasites of medical importance. Correlate between epidemiology and control of parasitic diseases halawakil39@gmail.com

Which of the following figures represent parasitism? B C A halawakil39@gmail.com

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MEDICAL PARASITOLOGY Is the science that deals with the parasites, which cause human infections and the diseases they produce. It is broadly divided into 2 parts € Protozoology € Helminthology. halawakil39@gmail.com

Parasites are living organisms, which depend on a living host for their nourishment and survival. They multiply or undergo development in the host. halawakil39@gmail.com

Parasites Types Hosts halawakil39@gmail.com

ECTOPARASITES ENDOPARASITES Infestation Infection Ectoparasite: Ectoparasites inhabit only the body surface of the host without penetrating the tissue Endoparasite: A parasite, which lives within the body of the host and is said to cause an infection Infection halawakil39@gmail.com

Permanent parasite Temporary parasite halawakil39@gmail.com

Facultative parasite Obligate parasite Facultative parasite: Organism which may either live as parasitic form or as free living form Obligate parasite: The parasite, which cannot exist without a host halawakil39@gmail.com

Aberrant parasite Accidental parasite Accidental parasites: Parasites, which infect an unusual host Aberrant parasites: Parasites, which infect a host where they cannot develop further halawakil39@gmail.com

Opportunistic parasites Parasites capable of producing a disease or flaring up of infection in a person with a poorly functioning immune response or with immune deficiency conditions (immunocompromised) Toxoplasma gondii Strongyloides stercoralis halawakil39@gmail.com

High host specificity parasites Low host specificity parasites Zoonosis WHO defined zoonosis as “those diseases and infections, which are naturally transmitted between vertebrate animals and man”. halawakil39@gmail.com

Host Intermediate host Definitive host The host, in which the adult parasite lives and undergoes sexual reproduction The host, in which the larval stage of the parasite lives or asexual multiplication takes place It is an organism, which harbors the parasite and provides nourishment and shelter to latter halawakil39@gmail.com

Vector It is usually an arthropod that transmits the parasites from one host to another Mechanical Biological No role in parasite development It is essential for parasite development Parasites are on vector body parts and are passively brushed off Parasites are within the vectors and transmission is through a bite halawakil39@gmail.com

Reservoir host Accidental host Paratenic host It is the animal that harbors an infection that can be transmitted to humans. The animals share the same stages of parasites with the human Zoonosis :diseases, which are naturally transmitted between vertebrate animals and man. Accidental host The host, in which the parasite is not usually found Paratenic host It is a host, in which larval stage of the parasite remains viable without further development halawakil39@gmail.com

EPIDEMIOLOGY & CONTROL halawakil39@gmail.com

FACTORS that influences the disease frequency Epidemiology of parasitic diseases FACTORS that influences the disease frequency PERSON, PLACE &TIME Study of the distribution and determinants of A parasitic disease among specified populations and the application of that study to the control of health problems By distribution, we mean who gets the disease, when and where or: Person-Place-time. By determinants, we mean causes and factors that influence the disease frequency in a population . halawakil39@gmail.com

Epidemiology & principles of control Source of infection: patients, carriers, reservoir hosts Route of infection Oral transmission Skin transmission Vector transmission Direct transmission Vertical transmission Iatrogenic transmission Susceptible population Contaminated soil and water Food Insect vectors halawakil39@gmail.com

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Epidemiology & principles of control(cont.) Endemic factors Natural factors Social factors Eating habits hygienic habit… Sexual transmitted diseases halawakil39@gmail.com

Epidemiology & principles of control(cont.) Principal of disease control Control the source of infection Cut off the route of transmission Massive protection, esp. for the susceptible population no successful vaccine halawakil39@gmail.com

Suggest the determinants and control measures of the following diseases halawakil39@gmail.com

Temperature and humidity Competent vector Breeding places Temperature and humidity halawakil39@gmail.com

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Learning resources Medical parasitology Part 1 ( by: Staff of Parasitology department )   -Paniker’s Textbook of Medical Parasitology: General introduction, Chapter 1: 1-8. halawakil39@gmail.com

halawakil39@gmail.com