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Parasitology

Parasitology. Mallory Smunk Katie Winkelman Bridget Weyer. What is a Parasite?. A parasite is an organism that depends on another organism, known as a host A parasite depends on its host for shelter and for food

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Parasitology

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  1. Parasitology Mallory SmunkKatie WinkelmanBridget Weyer

  2. What is a Parasite? • A parasite is an organism that depends on another organism, known as a host • A parasite depends on its host for shelter and for food • Parasitic infection may cause illness, disease and discomfort, or may show no signs at all

  3. What is a Parasite? • Classification of parasites • Ectoparasite- lives on the host’s body surface (Lice, Flea) • Endoparasite- lives inside the host’s body (Tapeworm, Roundworm)

  4. What is a Parasite? • Classification of parasites • Protazoa- single celled organisms • Helminths- wormlike organisms • Arthropods- organisms characterized by exterior skeletons and segmented bodies

  5. The History of Parasites • Early human ancestors had parasites, but until recently there was no evidence to support this claim. • Eggs of the lung fluke found in fossilized feces in Northern Chile (estimated 5900 B.C.) • Tapeworm eggs have been found present in Egyptian Mummies (estimated 2000 B.C.-1000 B.C.)

  6. The History of Parasites • First written records of parasitic infections come Egyptian medicine (3000 B.C.-400 B.C.) • Parsitology writings by Arabic physicians Rhazes (AD 850-923) and Avicenna (AD 980- 1037) clearly defined infections caused by parasites

  7. Bioterrorism & Argoterrorism • Parasites not as much of a threat • Intentional placement of parasites in food and water supplies could happen in the future

  8. The Future of Parasites • Researchers are trying to develop vaccines for parasites

  9. Dracunculus Medinensis

  10. Dracunculus Medinensis • threadlike parasitic worm that grows and matures in people. • Worms grow up to 3 feet long and are as wide as a paper clip wire. • Causes Dracunculiasis or Guinea Worm Disease.

  11. Dracunculus Medinensis • Occurs mostly in Africa • Contracted by drinking water that is contaminated by a water flea that is infected with the larvae of the Guinea Worm

  12. Dracunculus Medinensis • For the first year the immature worms cling to the walls of your intestines and mate. • After fertilization of female worms, the male dies. • Female worms will make there way through the body ending near lower limbs, maturing to 3 feet.

  13. Dracunculus Medinensis • Signs and Symptoms • Fever, pain and swelling in area where worm is about to emerge • Blister forms • When the wound is immerged in water the worm will emerge

  14. Dracunculus Medinensis • Guinea Worm treatment • Using a small stick, wrap around the end of the worm and remove little bits at a time • Treatment may take weeks or even months

  15. Hookworm

  16. Hookworm • Lives in small intestine of its host • Two types: • Ancylostoma duodenale • Necator americanus • Infects more than 600 million people worldwide

  17. Hookworm Ancylostoma duodenale • Worms are grayish white/pinkish with the head slightly bent in relation to the rest of the body • Two sets of teeth • Males 1 cm by 0.5 mm • Females much longer and stouter • Predominates in Middle East, North Africa, India, southern Europe

  18. Hookworm Necator americanus • Smaller than A. duodenale • Males usually 5-9 mm long • Females 1 cm long

  19. Hookworm Necator americanus • Possesses a pair of cutting plates in the buccal capsule • Hook shape is more define in Necator than in Ancylostoma • Predominates in Americas, Sub-Saharan Africa, Southeast Asia, China, and Indonesia

  20. Hookworm • Ground-itch, an allergic reaction at the site of parasitic penetration and entry • Cough and pneumonitis, may result as larvae begin to break into the alveoli and travel up trachea • Larvae reach the small intestine of host and begin to mature, the infected individual will suffer from diarrhea and other gastrointestinal discomfort

  21. Hookworm • Signs and symptoms • Can be linked to inflammation in the gut stimulated by feeding hookworms such as: • Nausea • Palpitations • Abdominal Pain • Anemia • Shortness of breath • Thready pulse • Edema

  22. Hookworm • The eggs can only hatch if the following conditions exist: • Thrives in warm earth where temperatures are over 18°C • Exist primarily in sandy or loamy soil and cannot live in clay or muck • Rainfall averages must be more than 1000mm a year • Necator americanus can survive at higher temperatures than Ancylostoma duodenale

  23. Hookworm

  24. Hookworm • Diagnosis • Finding characteristic worm eggs on microscopic examination of the stools, although this is not possible in early infection • Eggs are: • Oval or elliptical • 60 micrometers by 40 micrometers • Not bile stained • Thin transparent hyaline shell membrane

  25. Hookworm • Prevention • Do not defecate in places other than the restroom • Do not use human excrement or raw sewage or untreated ‘night soil’ as manure/fertilizer in agriculture • Do not walk barefoot in known infected areas • Deworm your pets

  26. Hookworm • Can be treated with local cryotherapy when it is still in the skin • Albendazole is effective both in the intestinal stage and during the stage the parasite is still migrating under the skin • Most common treatment: • Benzimidazoles (BZAs) (kills adult worms) • http://www.youtube.com/watch?v=BqAfhT11Ed8

  27. Giardia intestinalis

  28. Giardia Intestinalis • Parasite that causes the infection, Giardiasis (A.K.A Beaver Fever) • Effects up to 2.5 million people a year in the United States • Giardiasis is the most seen waterborne illness in people

  29. Giardia Intestinalis • Cysts are found in the feces of the infected and water contaminated by the infected • Spread person to person by contamination of food with feces, or by direct fecal-oral contamination

  30. Giardia Intestinalis • Diagnosed by examination of stool under microscope for cysts or trophozoites • Antigen testing of stool will identify up to 90% of people infected • Collection of fluid from the duodenum or biopsy of small intestine can also be tested

  31. Giardia Intestinalis • Signs and symptoms • Diarrhea in 60-90% of patients • Abdominal pain • Bloating • Nausea with or without vomitting • Malaise • Fatigue • Foul flatus • Burping • Halitosis- foul smelling breath • Lactose intolerance may occur in some cases

  32. Giardia Intestinalis • Preventive measures • Practice good hygiene • Avoid contaminated water • Avoid food that may be contaminated • Avoid fecal exposure during sexual intercourse, especially while experiencing diarrhea from giardiasis

  33. Giardia Intestinalis • Treatment for Giardiasis • Furoxene for 7-10 days (Only approved drug in U.S.) • Outside U.S. Tinidazole is approved for use • Metronidazole is most effective drug to treat Giardiasis, however, it is not FDA approved in the U.S.

  34. Liver & Lung Flukes

  35. Liver & Lung Flukes • Most important and recognized types of flukes are: • Paragonimus westermani, lung fluke that causes paragonmiasis • Clonorchis Sinensis, liver fluke that causes clonorchiasis • Opisthorcus spp., which causes opisthorchiasis

  36. Liver & Lung Flukes • Adult flukes are typically flat, oval-shaped • Layer of muscles just below the skin, that allows the worm to expand and contract it’s shape enabling it to move • Oral sucker on the anterior end, sometimes ringed with hooks, that it uses to attach itself to the host’s tissues

  37. Liver & Lung Flukes • Flukes are commonly found throughout Africa, South America, Middle-East, and Asia • Not common in North America but cases have been reported • Approximately 50 million cases worldwide

  38. Liver & Lung Flukes • Contracted by eating raw or undercooked crabs and crayfish or drinking from a contaminated water supply • Lung flukes travel to the small intestine and then migrate towards lungs • Fluke parasites lay eggs and cause inflammation and scar tissue to develop • These pockets of infection may rupture, causing infected person to cough up fluke eggs, blood, and inflamed lung tissue.

  39. Liver & Lung Flukes • Lung fluke symptoms • Chest pain • Fever • Abdominal pain • Diarrhea • Bloody sputum • Liver fluke symptoms • Chronic diarrhea • Abdominal pain • Ulcers • Liver damage • Toxemia can occur when host’s body absorbs the worm’s metabolites

  40. Liver & Lung Flukes • Only limited information is known about treating fluke infections • There are a few medications used to kill flukes: • Praziquantel • Niclosamide • Tetrachloroethylene

  41. Trichomoniasis

  42. Trichomoniasis • Sexually transmitted infection caused by the protozoa Trichomonas vaginalis • One of the most common STDs in the United States • Increases the risk of HIV transmission • Associated with adverse pregnancy outcomes, infertility, postoperative infections, and cervical neoplasia

  43. Trichomoniasis • The parasite is sexually transmitted through penis-to-vagina intercourse or vulva-to-vulva contact with an infected partner • Women can acquire the disease from infected men or women, but men usually contract it only from infected women

  44. Trichomoniasis

  45. Trichomoniasis • Approximately the size of a WBC • Flagellum allows it to move around vaginal and urethral tissues • Symptoms occur after an incubation period of 4-28 days

  46. Trichomoniasis • In women: • Isolated from the vagina, cervix, urethra, bladder, and Bartholin and Skene glands • In men: • Found in the anterior urethra, external genitalia, prostate, epididymis, and semen

  47. Trichomoniasis • Signs and Symptoms • Frothy, yellow-green vaginal discharge with a strong odor • Discomfort during intercourse and urination • Irritation and itching of female genital area • Lower abdominal pain

  48. Trichomoniasis • A health care provider must perform a physical examination and laboratory test • The parasite is harder to detect in men than women • In a pelvic examination of a female it may reveal small red ulcerations on the vaginal wall or cervix • http://www.youtube.com/watch?v=7j5Th5eqXko&NR=1

  49. Sources • Trichomoniasis. (2010). Wikipedia, the free encyclopedia. Retrieved from: http://en.wikipedia.org/wiki/Trichomoniasis • CDC fact sheet Trichomoniasis. (2007). What is trichomoniasis? Retrieved from: http://www.cdc.gov/std/trichomonas/stdfa ct-trichomoniasis.htm • Trichomoniasis. (2010). Emedicine. Retrieved from: http://emedicine.medscape.com/article/230617-print

  50. Sources • Guinea Worm Disease Facts. (n.d.). Retrieved August 12, 2010, from Department of Health Promotion and Education: http://www.dhpe.org/infect/guinea.html • Guinea-Worm Disease. (2010). Retrieved August 15, 2010, from World Health Organization: http://www.who.int/water_sanitation_health/diseases/guinea/en/

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