Protozoan disease

Presentation on Protozoan and Disease caused by them in humans. for more such content you can search on www.faunafondness.com

1. TOPIC :- PROTOZOAN PARASITES ENTAMOEBA HISTOLYTICA TRYPANOSOMA GAMBIENSE WWW.FAUNAFONDNESS.COM

2. SYNOPSIS 1. INTRODUCTION 2. ENTAMOEBA HISTOLYTICA – Morphology Life cycle Pathogenicity Treatment Control TRYPANOSOMA GAMBIENSE – Morphology Life cycle Pathogenicity Treatment Control CONCLUSION REFERENCES WWW.FAUNAFONDNESS.COM

3. 1.INTRODUCTION PROTOZOA – Protozoa is an informal term for single celled eukaryotic , either free- living or parasitic, which feed on organic matter. Protozoa vary substantially in size and shape . Many protozoa alternate between a free living vegetative from known as astrophozoite and a resting form called a cyst . Most protozoa have a single nucleus . Protozoa are heterotrophic microorganism . Many protozoal species move independently by one of three types of loco motor organelles: flagella, cilia, and pseudopodia . WWW.FAUNAFONDNESS.COM

4. 2.ENTAMOEBA HISTOLYTICA GEOGRAPHICAL DISTRIBUTION - Worldwide . More common in the tropics and subtropics than in the temperate zone . HABITAT - Trophozoite of E. histolytica live in the mucous and sub mucous layer of the large intestine. WWW.FAUNAFONDNESS.COM

5. MORPHOLOGY – There are 3 phases in the life cycle of E. histolytica – TROPHOZOITE ( Growing or feeding stage )- Shape – not fixed Size – range from 18-40 um Cytoplasm- a clear translucent ectoplasm and a granular endoplasm. Red blood cells , occasionally leukocyte and tissue debris are found inside the endoplasm. Nucleus – shape is spherical size is 4-6 um WWW.FAUNAFONDNESS.COM

6. 2) PRE- CYSTIC STAGE - Size – 10-20um Shape- round or slightly ovoid with a blunt pseudopodium projecting from the periphery. Endoplasm is free of red blood cells and other food particles. Nucleus structure is same as that of trophozoite . 3) CYSTIC – STAGE – Size – the small race being 6-9 um and large race 12-15 um. During encystment , the parasite become rounded and is surrounded by a highly refractile membrane , called CYST wall. Cytoplasm is clear and hyaline . In early stage of development cytoplasm of cyst shows- Chromatid or Chromidial Bars Glycogen Mass WWW.FAUNAFONDNESS.COM

7. WWW.FAUNAFONDNESS.COM

8. LIFE – CYCLE – It passes its life cycle only in 1 host-man. Infective stage : mature quadrinucleate cyst passed in feces of carrier and convalescent. The cyst can remain viable under moist condition for 10 days . Mode of transmission : man acquires infection by swallowing food and water contaminated with cysts. As the cyst wall is resistant to action of gastric juice , the cyst enters the small intestine undamaged. WWW.FAUNAFONDNESS.COM

9. When the cyst reaches caecum and lower part of the ileum ,due to the alkaline medium , the cyst wall damaged by trypsin leading to excystation. The cytoplasm gets detached from the cyst wall and amoeboid movements appear causing a tear in the cyst wall , through which quadrinucleate amoeba is liberated . This stage is called the METACYST . The nuclei in the metacyst immediately undergoes division to form 8 nuclei , each gets surrounded by its own cytoplasm forming metacyst trophozoites. WWW.FAUNAFONDNESS.COM

10. Life cycle of Entamoeba histolytica WWW.FAUNAFONDNESS.COM

11. PATHOGENECITY- Incubation period – 4-5 days. Symptomatology – term AMOEBIASIS is used to denote all those conditions which are produced in human host by infection with E. histolytica at different areas of its invasion. AMOEBIC DYSENTERY is a condition in which the infection is confined to the intestinal canal and is characterized by the passage of blood and mucus in the stool. WWW.FAUNAFONDNESS.COM

12. Dysentery is a symptom characteristics of extensive intestinal ulcerations representing only a part of the clinical picture of intestinal amoebiasis. Clinical picture vary from acute colitis to chronic colitis and asymptomatic carrier state. WWW.FAUNAFONDNESS.COM

13. TREATMENT – Three classes of drugs are used : Luminal amoebicides – iodoquinol , paromomycin and tetracycline act in the intestinal lumen but not in tissue. Tissue amoebicides – chloroquine is affective in systemic infection but less effective in the intestine. Both luminal and tissue amoebicides – metronidazole and related compounds act on both sites and are the drug of choice for treating amoebic colitis and amoebic liver abscess. WWW.FAUNAFONDNESS.COM

14. CONTROL – Wash hands thoroughly with soap and hot running water for at least 10 sec. after using toilet or changing a baby’s diaper and before handling food . Clean bathrooms and toilet ; pay particular attention to toilet seats and taps . Avoid sharing towels or face wash . TO HELP PREVENT INFECTION- Boil water or treat with iodine tablets . Avoid eating street foods especially in public where other are sharing sauces in one container . Avoid raw vegetables. WWW.FAUNAFONDNESS.COM

15. 3.TRYPANOSOMA GAMBIENSE Trypanosoma gambiense is a protozoan haemoflagellate endoparasite of man inhabiting the blood , lymph and the intercellular spaces of different tissues and organs of man . Hogs , goat, cattle and sheep are potential reservoir hosts. The parasite causes a disease called Gambian or West- African sleeping sickness in human beings. GEOGRAPHICAL DISTRIBUTION – T. gambiense are found in West and Central Africa . Their distribution depends upon the areas where the vector of the parasite, Glossina palpalis actually exists . WWW.FAUNAFONDNESS.COM

16. HABITAT – T. gambiense lives as a parasite in blood , lymph ,lymph node , spleen , or cerebrospinal fluid of man and in the intestine of blood sucking fly Glossina palpalis (Tsetse fly ). MORPHOLOGY – Shape and size : T. gambiense has a slender elongated , colorless , sickle – shaped and flattened microscopic body which is tapering at both the ends . Anterior end is pointed and posterior end is blunt . Body length varies from 15-30 micron and width from 1-3 micron . The shape and size of its body vary with the form in which it exists . WWW.FAUNAFONDNESS.COM

17. Pellicle and undulating membrane : The body is covered by a thin , elastic and firm pellicle . It maintains the general shape of the body . The pellicle is made up of fine fibril . Flagellum : Flagellum is single in Trypanosoma , i.e. , it is uniflagellate . The flagellum arises from the basal granule situated near the posterior end of the body. Kinetoplast : Just posterior to basal granule , there is a small , spherical or disc- shaped parabasal body or kinetoplast . Kinetoplast contains extra- nuclear DNA and hence, it is self – duplicating body . The kinetoplast is related to locomotion . WWW.FAUNAFONDNESS.COM

18. Cytoplasm : Its cytoplasm is differentiated into ectoplasm and endoplasm . The cytoplasm contains numerous granules called volutin granules . Cytoplasm also contains Golgi apparatus , mitochondria , ER and nucleus . Nucleus : A single , oval or spherical and vesicular nucleus (trophonucleus) is seen in the middle of its body . The nucleus contains a large endosome surrounded by chromatin. WWW.FAUNAFONDNESS.COM

19. WWW.FAUNAFONDNESS.COM

20. Polymorphic forms of T. gambiense : 1 . Leishmanial (amastigote ) – Small , oval surrounded body . Flagellum reduced , fiber –like embedded in the cytoplasm External flagellum is not found. Leptomonad (promastigote ): Elongated body . A free flagellum originated from the basal granule. No undulating membrane is formed . WWW.FAUNAFONDNESS.COM

21. 3. Crithidial (epimastigote ): Short , elongated but stumpy body . A long flagellum arises from basal granule and become free anteriorly . Undulating membrane ill- developed . 4. Trypanosome (trypomastigote ): Elongated and slender body . Flagellum is large and become free anteriorly . Undulating membrane is well developed . WWW.FAUNAFONDNESS.COM

22. LIFE CYCLE - The life cycle of T. gambiense is completed within two hosts i.e., digenetic ,a primary vertebrate (man) and secondary invertebrate (Tsetse fly ) host or vector. T. gambiense lives harmlessly in the blood of antelopes Part of life cycle in man : When an infected fly bites a man , it inoculates a few parasites in the blood of man . The parasites first live in the blood of infected man but later find their way into the cerebrospinal fluid . The parasites multiply by longitudinal binary fission in the blood and produce three form of individual= (1) Long and thin form’s with a free flagellum , (2) Short and stumpy form with a reduced flagellum and (3) Intermediate forms. WWW.FAUNAFONDNESS.COM

23. When a tsetse fly sucks the blood of an infected man , a number of parasites enters into the midgut of the fly along with the blood . These parasites remain in the midgut of fly for a few days and start multiplying by longitudinal binary fission. After 10-15 days , long slender forms appear in great number which move forward to the proventriculus . After several more days, the trypanosomes make their way to the fly’s salivary gland . These short and stumpy forms are capable of development in the intermediate host , Glossina palpalis . WWW.FAUNAFONDNESS.COM

24. Here the development continues for 2-5 days and the crithidial forms produce METACYCLIC FORM (TRYPANOSOME FORM )which are now infective . When the fly bites a man , the metacyclic forms enter the blood of man along with the saliva of the fly . The whole cycle in the fly usually takes 2-30 days . In the salivary glands they multiply by longitudinal binary fission and develop into crithidial forms(short flagellum and undulating membrane . WWW.FAUNAFONDNESS.COM

25. Life cycle of Trypanosoma gambiense WWW.FAUNAFONDNESS.COM

26. PATHOGENICITY- The bite of an infected fly is usually followed by itching and irritation near the wound . In blood the parasite multiplies and absorbs nutrient from it .After few days fever , headache ,weakness ,loss of weight and anaemia occur. Usually the parasites succeed in penetrating the lymphatic glands . Because of its infection , the lymphatic glands swell and after it the parasites enter the cerebrospinal fluid and brain causing a sleeping sickness like condition. WWW.FAUNAFONDNESS.COM

27. TREATMENT - In early infection drugs like suramin (Bayer 205 )and pentamidine are used . In later stage when central nervous system is involved arsenicals like tryparsamide , melarsen and tnmelarsen are being used. Nitrofurazone (fiiracin) may be used in certain cases . WWW.FAUNAFONDNESS.COM

28. CONTROL- Control breeding sites . Insecticides Treatment of human cases General cleanliness Protection against bites WWW.FAUNAFONDNESS.COM

29. 4. CONCLUSION Entamoeba histolytica is an anaerobic parasitic amoebozoan , part of the genus Entamoeba . Predominantly infecting humans and other primates causing amoebiasis . E. histolytica is estimated to infect about 50 million people worldwide . Trypanosoma gambiense is a protozoan haemoflagellate endoparasite of man inhabiting the blood , lymph and the intercellular spaces of different tissues and organs of man. The parasite causes a disease called Gambian or West- African sleeping sickness in human beings. WWW.FAUNAFONDNESS.COM

30. THANK YOU WWW.FAUNAFONDNESS.COM