faculty of allied medical science parasitology ( mlpr-201) fall 2013/2014
Post on 15-Jan-2016
54 Views
Preview:
DESCRIPTION
TRANSCRIPT
Dr. Hamdy Badie M. El-Wakil
Prof. of Parasitology & Public Health .
Faculty of Allied Medical Sciences.Pharos University In Alexandria,Egypt
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.
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.
4
Parasite Diseases No. people infected Deaths/yr
Plasmodium malaria 273 million 1.12 million
Soil transmitted helminthes:
• Roundworm (Ascaris)
• Whipworm (Trichuris)• • Hookworm
(Ancylostoma and Necator)
Pnemonitis, intestinal obstruction
Bloody diarrhoea, rectal prolapse
Coughing, wheezing, abdominal pain and anaemia
2 billion 200,000
Schistosoma Renal tract and intestinal disease
200 million 15,000
Filariae Lymphatic filariasis and elephantiasis
120 million Not fatal but 40 million disfigured or incapacitated
Trypanasoma cruzi Chagas disease (cardiovascular)
13 million 14,000
African trypanosomes African sleeping sickness 0.3 – 0.5 million 48,000
Leishamania Cutaneous, mucocutaneous and visceral leishmaniasis
12 million; 2 million new cases/yr
50,000
5
6
Phylum: Sarcomastigophora:Phylum: Sarcomastigophora:
Subphylum: Sarcodina e.g. Subphylum: Sarcodina e.g. AmoebaAmoeba
Subphylum:Mastigophora e.g. Subphylum:Mastigophora e.g. TrypansomaTrypansoma
Phylum: Ciliphora: Class: Ciliates e.g. Phylum: Ciliphora: Class: Ciliates e.g. Balantidium coliBalantidium coli
Phylum: Apicomplexa: Class: Sporozoa e.g. Phylum: Apicomplexa: Class: Sporozoa e.g. PlasmodiumPlasmodium Sp. Sp.
Classification of parasites and vectorsClassification of parasites and vectors
Animal KingdomAnimal Kingdom
Sub-KingdomSub-Kingdom(Metazoa)(Metazoa)
Multicellular animalsMulticellular animals
Sub-KingdomSub-Kingdom(Protozoa) Unicellular (Protozoa) Unicellular
parasites=kingdom parasites=kingdom
ProtistaProtista
Phylum Helminthes : Phylum Arthropods :Phylum Phylum Helminthes : Phylum Arthropods :Phylum MolluscsMolluscs
7
Sub kingdom =kingdom =kingdom ProtistaProtista
Phylum Sub-phylum Genus- examples
Species- examples
Unicellular Unicellular Protozoa
Sarcomastig-ophorafurther divided into
Sarcodina-- - move by pseudopodia
Entamoeba E. histolytica
Mastigophoramove by flagella
Giardia G. lamblia
Apicomplexano organelle of
locomotion
Plasmodium P. falciparum,
P. vivax,
P. malariae,
P. ovale
Ciliophoramove by cillia
Balantidium B. coli
MicrosporaSpore-forming
Enterocyto-zoa
E. bieneusi
Sub kingdom
Phylum Class Genus – examples
Metazoa
Multicellular Multicellular animalsanimals
NematodesRound worms; appear round in cross section, they have body cavities, a straight alimentary canal and an anus
Ascaris (roundworm)
Trichuris (whipworm)
Ancylostoma (hookworm)
Necator (hookworm)
Enterobius (pinworm or threadworm)
Strongyloides
Platyhelminthes or PlathelminthesFlat worms; dorsoventrally flattened, no body cavity and, if present, the alimentary canal is blind ending
CestodesAdult tapeworms are found in the intestine of their host
They have a head (scolex) with sucking organs, a segmented body but no alimentary canal
Each body segment is hermaphrodite
Taenia (tapeworm)
TrematodesNon-segmented, usually leaf-shaped, with two suckers but no distinct head
They have an alimentary canal and are usually hermaphrodite and leaf shaped
Schistosomes are the exception. They are thread-like, and have separate sexes
Fasciolopsis (liver fluke)
Schistosoma (not leaf shaped!)
8
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
9
10
Parasite transmissionParasite transmission
IndirectIndirect(with intermediate hosts)(with intermediate hosts)
DirectDirect
(without intermediate host)(without intermediate host)
(2) Immediately(2) Immediately
infectiveinfective Entamoeba histolyticaEntamoeba histolytica
Giardia lambliaGiardia lamblia
Balantidium coliBalantidium coli
Trichomonas Trichomonas spsp
.. Hymenolepis nanaHymenolepis nana
Enterobius vermicularisEnterobius vermicularis
Sarcoptes scabieiSarcoptes scabiei
Pediculus huminusPediculus huminus
Phthirus pubisPhthirus pubis
(1)Taking a (1)Taking a period to period to become become
infectiousinfectiousAscaris lumbricoidesAscaris lumbricoides
Trichuris trichiuraTrichuris trichiura
Ancylostoma duodenaleAncylostoma duodenale
Necator americanaNecator americana
Strongyloides stercoralisStrongyloides stercoralis
(2) Requiring (2) Requiring oneone
intermediate intermediate hosthost
Wuchereria bancroftiWuchereria bancrofti
Onchocerca volvulusOnchocerca volvulus
Loa loaLoa loa
Dracunculus medinensisDracunculus medinensis
Dipylidium caninumDipylidium caninum
Taenia Taenia sppspp
.. Schistoma Schistoma sppspp
.. Leishmania Leishmania spp.spp.
Fasciola spp.Fasciola spp.
((1) Requiring 1) Requiring TwoTwo
intermediate intermediate hostshosts
• H. HetrophyesH. Hetrophyes
Clonorchis sp.Clonorchis sp.
Fasciolopsis buskiFasciolopsis buski
Paragonimus Paragonimus westermaniwestermani
Diphyllobothrium Diphyllobothrium L.L.
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
11
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
12
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.
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.
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.
Definitions: What is ….?
Endemic parasite:
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.
Define the following:
Definitive host: Intermediate host Zoonosis: Vector: Commensal:
Group of students will be selected for an assignment topic ,one of the parasites that are studied in your course.
The following points should be covered in your assignment sheets:
(1) Classification Position:(2) Name of the parasite;(3)Description ( Morphological Characters in vivo): (4) Definitive (Final) Host:(5) Intermediate Host:(6) Mode Of Infection:(7) Infective Stage:-.(8) Habitat:- (9) Diagnostic Stage:- (10) Disease:- (11) life cycle
Giardia lamblia.
Should be prepared by the following students Ahmed Hassan Hameda Ahmed Raslan Ahmed Farghaly Ahmed Mahfouz Amr Abdel Attey Amr Salah Al Dein khalaf Amr Youness Ghaly Moursy
Ahmed Mohamed Abdel Hameed Ahmed Abdel Naby Akhlas Khalil Esraa Farhat Faten Lotfy Fatma Soubhy Fatma Mohamed Khalil Kareem Zeddan
top related