Parasitology and Medical Entomology Fall 2024-2025 Lecture 1 PDF

# Parasitology and Medical Entomology - Fall 2024–2025 ## Course Information - **Course Title:** Parasitology and Medical Entomology - **Course Code:** 040510263 - **Department:** Zoology department, Faculty of Science, Alexandria University - **Level:** 2nd level ## Introduction Parasitology is...

# Parasitology and Medical Entomology - Fall 2024–2025 ## Course Information - **Course Title:** Parasitology and Medical Entomology - **Course Code:** 040510263 - **Department:** Zoology department, Faculty of Science, Alexandria University - **Level:** 2nd level ## Introduction Parasitology is a branch of biological science that is concerned with parasites and parasitism. Parasitism is a form of symbiosis in which one organism (called parasite) benefits at the expense of another organism usually of different species (called host). The association may also lead to the injury of the host. ## History - **Antonie van Leeuwenhoek (1626-1697),** a pioneer Dutch microscopist, first introduced the single lens microscope in 1681 and observed Giardia in his own stools. - **Francesco Redi** (18 February 1626 ­– 1 March 1697) is recognized as the "father of modern parasitology". He was a key figure in experimental biology and is considered the father of modern parasitology because of his works and contributions to the field. He was able to identify and describe several parasites. ## Course Objectives The course aims to provide the major concepts of parasitology and medical entomology. The course will cover: - Protozoology: - Sarcomastigophora - Apicomplexa - Microspora - Myxozoa - Ciliophora - Helminthology: - Helminthes (Flatworms & roundworms) - Acarina (Ticks, some mites) - Insects of medical importance - The role of insects and other arthropods in human and animal health - Filth flies and human diseases: - Fleas - House flies - Beds bugs - Blowflies - Horse fly - Lice - Sandfly - Mosquitoes - Human diseases - Myiasis: maggot infestation ## Course Description - The course begins with a general introduction to parasitology. - The course covers the classification of parasites including: - Types of hosts and parasites. - Nomenclature of the parasitic organism. - Air-borne, water & food borne and insect borne diseases with detailed examples. - Epidemiology, pathogenicity, method of transmission, life cycle, symptoms of diseases, diagnosis and treatment: - Protozoology - Sarcomastigophora - Apicomplexa - Microspora - Myxozoa - Ciliophora - Helminthology (Flatworms & roundworms) ## Course Schedule | Week | Dates | Notes | |---|---|---| | 1 | Sep 21 - Sep 26 | Early registration | | 2 | Sep 28 - Oct 03 | Registration and Start of the course | | 3 | Oct 05 - Oct 10 | Class - Last date for adding/deleting courses: Oct 10, 2024 | | 4 | Oct 12 - Oct 17 | Class | | 5 | Oct 19 - Oct 24 | Quiz 1 & Class | | 6 | Oct 26 - Oct 31 | Class | | 7 | Nov 02 - Nov 07 | Class | | 8 | Nov 09 - Nov 14 | Class | | 9 | Nov 16 - Nov 21 | Mid-Term Exam | | 10 | Nov 23 - Nov 28 | Class + Oral Exam | | 11 | Nov 30 - Dec 05 | Class + Oral Exam | | 12 | Dec 07 - Dec 12 | Class + Oral Exam + 2 Quizzes | | 13 | Dec 14 - Dec 19 | Class | | 14 | Dec 21 - Dec 26 | Class + Practical Exams | | 15 | Dec 28 - Jan 02, 2025 | Class + Practical Exams | | 16 | Jan 04 - Jan 09, 2025 | Class + Final Exams | | 17 | Jan 11 - Jan 16, 2025 | Final Theoretical Exam | | | Jan 18 - Jan 23, 2025 | | **Note:** Official holidays during Fall 2024-2025 will be in accordance with the Prime Minister's decisions. ## Course Assessment - **Quizzes:** 10% (weeks 4 & 11) - **Mid-Term Exam:** 10% (week 8) - **Oral Exam:** 10% (week 11) - **Practical Exam:** 20% (week 13) - **Final Exam:** 50% (week 15) **Total: 100%** ## Textbook Readings - CK Jayaram Paniker, 2018. *Paniker's Textbook of medical parasitology*. Eighth edition. The Health Sciences Publisher New Delhi I London I Panama - F. E. G. cox 1993. *Modern Parasitology*. Second Edition. Blackwell Science - P.J. Gullan and P.S. Cranston 2004. *The Insects An Outline of Entomology*. © 2005 by Blackwell Publishing Ltd - https://openstax.org/books/microbiology/pages/5-1-unicellular-eukaryotic-parasites - https://openstax.org/books/microbiology/pages/5-2-parasitic-helminths/ ## Lesson 1: General Introduction: Parasitology - Diagram of pathogenic protozoan parasites of man - Information regarding the host organism: - **Parasite:** A living organism that lives in or upon another organism (host) and derives nutrients directly from it, without giving any benefit to the host. Protozoa and helminthes (animal parasites) are studied in Medical Parasitology. - **Ectoparasite:** Inhabits the surface of the body of the host without penetrating into the tissues. They are important vectors transmitting the pathogenic microbes. The infection by these parasites is called as infestation, e.g fleas or ticks. - **Endoparasite:** Live within the body of the host (e.g., Leishmania). Invasion by an endoparasite is called infection. - **Types of endoparasites:** - **Obligate parasite:** Cannot exist without a parasitic life in the host (e.g., Plasmodium species) - **Facultative parasite:** Can live a parasitic life or free-living life, when the opportunity arises (e.g., Acanthamoeba) - **Accidental parasite:** Infects an unusual host (e.g., Echinococcus granulosus infects humans accidentally) - **Aberrant parasite or wandering parasite:** Infects a host where they cannot live or develop further (e.g., Toxocara in humans). - **Host:** An organism that harbors the parasite and provides nourishment and shelter. There are several different types of hosts: - **Definitive Host:** Where adult parasites replicate sexually (e.g., Anopheles species). - **Intermediate Host:** Where parasites undergo asexual multiplication (e.g., in malaria parasite - humans are the intermediate host). - **Reservoir Host:** Harbors the parasites and serves as a source of infection for other susceptible hosts. (e.g., dog is the reservoir host for cystic echinococcosis) - **Paratenic Host:** Where the parasite lives but cannot develop further (e.g., fresh water prawn for Angiostrongylus cantonensis) - **Amplifier Host:** Where the parasite lives and multiplies exponentially. - **Host-parasite relationship:** - **Symbiosis:** Close association between the host and the parasite where both are interdependent (e.g. none suffers any harm from each other) - **Commensalism:** One organism benefits, the other is neither harmed nor helped (e.g. a commensal is capable of living an independent life) - **Parasitism:** One organism benefits, the other is harmed (e.g. the host gets no benefit in return.) - **Transmission of parasites:** - **Sources of Infection:** - **Man:** Humans can be a source or reservoir for parasitic infections (e.g., amoebiasis, giardiasis, etc.) and the infection transmitted from one infected person to another is called anthroponoses. - **Animals:** The infection transmitted from infected animals to humans is called zoonoses (e.g., cystic echinococcosis from dogs and toxoplasmosis from cats) - **Vectors:** A vector is an agent, usually an arthropod that transmits the infection from one infected human to another. - **Modes of Transmission:** - **Oral or feco-oral route:** The most common mode, ingestion of food, water or vegetables contaminated with feces. - **Penetration of the skin and mucous membranes:** Larval forms of the parasite enter through unbroken skin (e.g., filariform larva of Strongyloides stercoralis and hookworm). - **Bloodsucking insect vectors:** Introduction of the parasites via a bite (e.g., Plasmodium species, Leishmania species and Wuchereria bancrofti) - **Sexual contact:** Trichomonas vaginalis is the most frequent parasite to be transmitted sexually. Entamoeba, Giardia and Enterobius can also be transmitted rarely by sexual contact. - **Bite of vectors:** Many diseases are transmitted by insect bite, e.g. malaria (female Anopheles mosquito), filariasis (Culex), leishmaniasis (sandfly), Chagas' disease (reduviid bug) and African sleeping sickness (tsetse fly) - **Vertical transmission:** Mother to fetus (e.g., Toxoplasma gondii, Plasmodium spp. and Trypanosoma cruzi) - **Blood transfusion:** Certain parasites can be transmitted through transfusion of blood or blood products. - **Autoinfection:** Few intestinal parasites may be transmitted to the same person by contaminated hand or by reverse peristalsis (e.g. Cryptosporidium parvum, Taenia solium, Enterobius vermicularis, Strongyloides stercoralis and Hymenolepis nana). - **Life cycle of the parasites:** - **Direct (Simple):** When a parasite requires only one host to complete its development. - **Indirect (Complex):** When a parasite requires two hosts (one definitive host and another intermediate host) to complete its development. - **Taxonomy of Amoeba** | Kingdom | Subkingdom | Phylum | Class | Order | Genus | |---|---|---|---|---|---| | Protozoa | Neozoa | Amoebozoa | Entamoebidea | Euamoebida | Entamoeba <br> Endolimax <br> Iodamoeba | | - | Percolozoa | - | Amoebaea <br> Heterolobosea (flagellated amoeba) | Acanthopodida <br> Schizopyrenida | Acanthamoeba <br> Naegleria | - **Free-living protozoa and human disease:** Most free-living protozoa have little to no impact on human health. - Free-living protozoa can be found throughout the environment. - Free-living amebae can cause pathology if introduced into the human host. - Some free-living protozoa produce toxins which can cause disease. - **Pathogenic free-living Amebae:** - **Naegleria fowleri:** Causes acute primary amebic meningoencephalitis (PAM). - **Acanthamoeba castellanii:** Causes chronic granulomatous amebic encephalitis (GAE), amebic keratitis, granulomatous skin and lung lesions. - **Naegleria Life Cycle:** Diagram - **Trophozoite:** The feeding and replicating form. - **Cyst:** The dormant form. - Diagram illustrating the infection of _Naegleria fowleri_. - **Acanthamoeba castellanii:** Free-living amebas that inhabit soil and water; cyst stages can be airborne; cause serious corneal ulcers; are being reported in individuals who use contact lenses and are presumably transmitted in contaminated lens-cleaning solution. - **Naegleria fowleri:** Inhabit bodies of fresh water and are responsible for almost all cases of primary amebic meningoencephalitis. It is thought to enter the body from water splashed onto the upper nasal tract during swimming or diving. - **Slides illustrating the lifecycle of Acanthamoeba castellanii:** - **Acanthamoeba castellanii** can also cause infections in animals. - **Parasites and their developmental stages found in stools:** List of parasites. - **Parasites found in peripheral blood:** List of parasites. - **Antigen detection in parasitic diseases:** - **Galactose lectin antigen:** Entamoeba histolytica - **Giardia-specific antigen 65:** Giardia lamblia - **WKK and rk39 antigen:** Leishmania donovani - **HRP-2 antigen:** Plasmodium falciparum - **Vivax specific pLDH:** Plasmodium vivax - **Principal protozoan parasites of man:** Table listing parasite species, habitat and disease caused. - **Principal protozoan parasites of man:** Table listing parasite species, habitat and disease caused (continued). ## Summary This document is a syllabus for a parasitology course. It covers the basics of the field, including the history of parasitology, different types of parasites, host-parasite interactions, transmission mechanisms, life cycles, and common parasites that cause disease in humans. The document also includes a schedule for the course, assessment details, and textbook readings. This syllabus is heavily image-based, containing many images of different parasites, life cycles, and other topics related to parasitology.