1. HELMINTH PART II
DR SAMUEL AGUAZIM

2. CESTODE TAPE WORM TAENIA SAGINATA INTERMEDIATE HOST: CATTLE
DEFINITIVE HOST: HUMANS
FORMS/TRANSMISSION
- Rare beef containing cysticerci is ingested
Interstinal tapeworm( affects small intestine)
Asymptomatic to vague abdominal pain
Chronic indigestion
Diagnosis: eggs or proglottids in feces
Treatment: praziquantel

3. TAENIA SOLIUM INTERMEDIATE HOST: SWINE DEFINITIVE HOST: HUMANS
Humans can be both intermediate and definitive host.
Forms/transmission
Intestinal tape worm
Raw pork containing the cysticerci ingested by humans

4. CYSTICERCOSIS(INTERMEDIATE HOST): Humans ingest eggs directly.
Water and food contaminated with eggs auto inoculation.
disease/organ involvement/symptoms
-intestinal tapeworm( same as taenia saginata)
Larvae penetrate intestinal wall and migrate via the blood to brain, heart, lungs and eye
Diagnosis: eggs or proglottids in feces
Treatment: praziquantel…

5. T. SOLIUM
T. SAGINATA

6. MOT: INGESTION OF CYSTICERCUS (larval worm) IN PORK/BEEF PRODUCTS

7. CT Scan of Cysticercosis

8. DIPHYLLBOTHRIUM LATUM
INTERMEDIATE HOST: CRUSTACEANS
DEFINITIVE HOST: HUMANS, MAMMALS
HUMANS can be both IH & DH
Forms/transmission
SPARGANUM
Drinking pond water with copepods crustaceans carrying the larval forms
Intestinal tape worm
Rare, eating raw prickled fish containing sparganum

9. FISH TAPEWORM Diphyllobothrium latum
longest tapeworm found in man
3-10 meters with more than 3000 proglottids.

10. Fish tapeworm:
Scolex has two elongated sucking grooves; no circular suckers or hooks

11. Fish tapeworm:
Oval eggs have an operculum (lidlike opening) at one end

12. MOT: INGESTION OF PLEROCERCOID LARVAE/SPARGANUM IN INFECTED FISH

13. Copepod

14. Disease/organ involvement/symptoms
Sparganosis: larvae penetrate intestinal wall and encyst
Interstinal tape worm in the small intestine that absorb vitamin B12 leading to PERNICIOUS ANEMIA
DIAGNOSIS: Eggs or proglottids in feces
Biopsy for sparganosis
Treatment: praziquantel

15. Echinococcus granulosus( dog tape worm)
INTERMEDIATE HOST: HERBIVORES
DEFINITIVE HOST: Carnivores in sheep- raising area
Humans are intermediate hosts
Forms/ transmission
Ingestion of eggs
Larvae can migrate to anywhere( liver is the most common place)

16. Dog tapeworm. Scolex has four suckers and a double circle of hooks.

17. Disease: HYDATID CYST DISEASE
Liver and lungs where cyst containing brood capsules develop
Eggs are ingested by sheep (and humans) and hatch larvae in the gut that migrate in the blood to various organs, especially the liver and brain.
Larvae form one large, unilocular hydatid cyst containing many minor pathogen and daughter cysts.
Diagnosis- imaging and serology
Treatment: surgery and albendazole

18. Echinococcus multilocularis
IH: RODENTS
DH: CANINES & CATS
HUMANS are intermediate hosts
Forms/transmission
Ingestion of eggs
Larvae can migrate to anywhere( liver is the most common place)

19. Disease: ALVEOLAR HYDATID CYST DISEASE
Much more serious than echinococcus granulosus : cyst metastasis: exogenous budding cyst
Diagnosis: difficult: MRI OR CT
TREATMENT: SURGICAL RESECTION

21. E. Multilocularis multilocular, liver

22. Hymenolepis nana (dwarf tapeworm)
most frequently diagnosed cestode infection in theUS
small tapeworm
infects children
Reservoirs: Rodents
vague abdominal pain  enteritis
Diagnosis :eggs
DOC: Nicolsamide

23. MOT: INGESTION OF EGGS/ CYSTICERCOID IN INSECTS

24. Spirometra sparganosis
MOT: ingest polluted water raw or inadequately cooked flesh of snakes or frogs
southeastern region of the United States
east Asia (China, Japan, and Korea)
southeast Asia (Malaysia, India, and the Philippines)

25. Sparganosis subcutaneous edema Muscles Eyes urogenital system
abdominal viscera
central nervous system

26. Sparganosis Treatment Surgical removal of sparganum larvae
Praziquantel
no available treatment for proliferative sparganosis

28. Trichuris trichiura Disease: Whipworm infection
Characteristics: Intestinal nematode. The characteristic of “whiplike” apperance of the adult worm.
Life cycle:
Humans ingest eggs, which develop into adults in gut.
Eggs are passed in feces into soil, where they embryonate, ie, become infectious.

29. Trichuris trichiura Transmission: More than 500 million infected.
Transmitted by food or water contaminated with soil containing eggs.
Humans are the only hosts. Occurs worldwide, especially in the tropics.
  Pathogenesis:
Worm in gut usually causes little damage.
The whipworm infects about 2 million children in the U.S.
Causes rectal pruritis and tenesmus, which often results in rectal prolapse.

30. Infectious Diseases Whipworm – Rectal Prolapse

31. Infectious Diseases Whipworm – Rectal Prolapse

32. Laboratory Diagnosis:
Eggs visible in feces.
The egg is barrel-shape with a plug at each end, in the stool.
Treatment: Mebendazole.
Prevention: Proper disposal of human waste

33. FOOTBALL SHAPE EGG
Trichuris trichiura eggs, a typical barrel shape two polar plugs, that are
unstained 

34. LOA LOA
Disease: Loiasis. Characteristics: Tissue nematode.

36. Transmission: Transmitted by deer flies
Transmission: Transmitted by deer flies. Humans are the only definitive hosts. No animal reservoir. Endemic in central and west Africa.
Pathogenesis: Hypersensitivity to adult worms causes “swelling” in skin. Adult worm seen crawling across conjunctivas
Laboratory Diagnosis:
Microfilariae visible on blood smear.
Treatment: Diethylcarbamazine.
Prevention: Deer fly control.

37. Onchocerca Disease: Onchocerciasis (river blindness).
Characteristics: Tissue nematodes.

38. Onchocerca
Transmission: Transmitted by female black flies. Humans are the only definitive hosts. No animal reservoir. Endemic along rivers of tropical Africa and Central America. Pathogenesis: Microfilariae in eye ultimately can cause blindness. Adults induce inflammatory nodules in skin. Laboratory Diagnosis: Microfilariae visible in skin biopsy, not in blood. Treatment: Ivermectin affects microfilariae, not adult worms. Suramin for adult worms. Prevention: Black fly control and ivermectin

39. RIVER BLINDNESS/SOWDA
trapped microfilaria in the cornea, choroid, iris and anterior chambers, leading to photophobia, lacrimation and blindness

40. Toxocara canis Disease: Visceral larva migrans.
Characteristics: Nematode larvae cause
disease.

41. Life cycle:
Toxocara eggs are passed in dog feces
Ingested by humans.
Hatch into larvae in small intestine
Larvae enter the blood and migrate to organs, especially liver, brain, and eyes, where they are trapped and die.
Transmission:
ingestion of eggs in food or water contaminated with dog feces.
Dogs are definitive hosts. Humans are dead end hosts.
Pathogenesis: Granulomas form around dead larvae. Granulomas in the retina can cause blindness

42. Laboratory Diagnosis: Larvae visible in tissue. Serologic tests useful.
Treatment: Diethylcarbamazine
Prevention: Dogs should be dewormed

43. Tissue nematode Dracunculus
 Disease: Dracunculiasis.
Characteristics: Tissue nematode.

44. Dracunculiasis

46. Transmission:
copepods in drinking water.
Humans are definitive hosts.
Many domestic animals are reservoir hosts.
Endemic in tropical Africa, Middle East, and India
Pathogenesis:
Adult worms in skin cause inflammation and ulceration.
Treatment:
Niridazole.
Extraction of worm from skin ulcer.
Prevention:
Purification of drinking water

47. Dracula ate an infected crustacean and got an ulcer with protruding worm.
He removed the worm by winding it around a stick.

48. Strongyloides Disease: Strongyloidiasis
Characteristics: Intestinal nematode.
NOTE: the only helminth to secrete larvae (and not eggs) in feces

49. Transmission: Filariform larvae in soil penetrate skin
Transmission: Filariform larvae in soil penetrate skin. Endemic in the tropics.
Pathogenesis:
Little effect in immunocompetent persons.
In immunocompromised persons, massive superinfection can occur accompanied by secondary bacterial infections.
  Laboratory Diagnosis: Larvae visible in stool. Eosinophilia occurs.
  Treatment: Thiabendazole.
Prevention: Proper disposal of human waste. Use of footwear

50. Memory Tool
The strongman (Strongyloides) is brought down by a larvae penetrating his skin causing pulmonary distress and superinfection. Poor strongman!

51. ANCYLOSTOMA BRAZILIENSE ANCYLOSTOMA CANINUM
DOG and CAT Hook worm
Forms/ Transmission.
Filariform larvae penetrate intact skin but cannot mature in humans
Disease/organ most affected
Cutaneous larvae migrans: intense itching
Tunnels through tissue
Diagnosis: clinical signs
Treatment- ivermectin