2 CESTODE TAPE WORM TAENIA SAGINATA INTERMEDIATE HOST: CATTLE DEFINITIVE HOST: HUMANSFORMS/TRANSMISSION- Rare beef containing cysticerci is ingestedInterstinal tapeworm( affects small intestine)Asymptomatic to vague abdominal painChronic indigestionDiagnosis: eggs or proglottids in fecesTreatment: praziquantel
3 TAENIA SOLIUM INTERMEDIATE HOST: SWINE DEFINITIVE HOST: HUMANS Humans can be both intermediate and definitive host.Forms/transmissionIntestinal tape wormRaw 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 eyeDiagnosis: eggs or proglottids in fecesTreatment: praziquantel…
8 DIPHYLLBOTHRIUM LATUM INTERMEDIATE HOST: CRUSTACEANSDEFINITIVE HOST: HUMANS, MAMMALSHUMANS can be both IH & DHForms/transmissionSPARGANUMDrinking pond water with copepods crustaceans carrying the larval formsIntestinal tape wormRare, eating raw prickled fish containing sparganum
9 FISH TAPEWORM Diphyllobothrium latum longest tapeworm found in man3-10 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
14 Disease/organ involvement/symptoms Sparganosis: larvae penetrate intestinal wall and encystInterstinal tape worm in the small intestine that absorb vitamin B12 leading to PERNICIOUS ANEMIADIAGNOSIS: Eggs or proglottids in fecesBiopsy for sparganosisTreatment: praziquantel
15 Echinococcus granulosus( dog tape worm) INTERMEDIATE HOST: HERBIVORESDEFINITIVE HOST: Carnivores in sheep- raising areaHumans are intermediate hostsForms/ transmissionIngestion of eggsLarvae 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 developEggs 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 serologyTreatment: surgery and albendazole
18 Echinococcus multilocularis IH: RODENTSDH: CANINES & CATSHUMANS are intermediate hostsForms/transmissionIngestion of eggsLarvae 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 cystDiagnosis: difficult: MRI OR CTTREATMENT: SURGICAL RESECTION
23 MOT: INGESTION OF EGGS/ CYSTICERCOID IN INSECTS
24 Spirometra sparganosis MOT: ingest polluted water raw or inadequately cooked flesh of snakes or frogssoutheastern region of the United Stateseast Asia (China, Japan, and Korea)southeast Asia (Malaysia, India, and the Philippines)
25 Sparganosis subcutaneous edema Muscles Eyes urogenital system abdominal visceracentral nervous system
26 Sparganosis Treatment Surgical removal of sparganum larvae Praziquantelno 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.
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 conjunctivasLaboratory Diagnosis:Microfilariae visible on blood smear.Treatment: Diethylcarbamazine.Prevention: Deer fly control.
38 OnchocercaTransmission: 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
41 Life cycle:Toxocara eggs are passed in dog fecesIngested by humans.Hatch into larvae in small intestineLarvae 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: DiethylcarbamazinePrevention: Dogs should be dewormed
46 Transmission:copepods in drinking water.Humans are definitive hosts.Many domestic animals are reservoir hosts.Endemic in tropical Africa, Middle East, and IndiaPathogenesis: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 ToolThe 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 wormForms/ Transmission.Filariform larvae penetrate intact skin but cannot mature in humansDisease/organ most affectedCutaneous larvae migrans: intense itchingTunnels through tissueDiagnosis: clinical signsTreatment- ivermectin