Eukaryotic MicrobesSlide 2ProtozoaSlide 4AmoebaAmoebaeEntamoeba histolyticaSlide 8Slide 9Acanthamoeba and NaegleriaSlide 11FlagellateSlide 13HemoflagellatesCiliatesSlide 16Slide 17Apicomplexans (Sporozoa)PlasmodiumSlide 20Cryptosporidium parvumCryptosporidium life cycleSlide 23Slide 24Helminths - wormsNematodes- RoundwormsFeatures of the Life Cycle of RoundwormsNematodes - roundwormsSlide 29Pinworm disease is the most prevalent helminthic infection in the United StatesEnterobius - PinwormSlide 32Necator or Ancylostoma - HookwormSlide 34Slide 35Filariasis is a lymphatic system infectionPlatyhelminthes - FlatwormsTrematodes - FlukesSchistosoma – blood flukeCestodes - TapewormsSlide 41A few other tapeworms also cause diseaseEchinococcusArthropods as VectorsSlide 45Arthropod VectorsScabies - miteArachnidsSlide 49InsectsSlide 51Eukaryotic Microbe ParasitesEukaryotic MicrobesParasitesProtozoa, Helminths, ArthropodsEukaryotic MicrobesTable 12.1Protozoa•Life Stages ––Trophozoite -vegetative; feeding, mostly motile–Cyst – dormant; protective thick wall•Most are free living in water and soil •Classified by motility & life cycle•Subdivided by location in human host (GI, blood, GU)1. Sarcodina- Amoeba - move by pseudopods2. Ciliophora - Ciliates - move by cilia3. Mastigophora - Flagellates - move by flagella4. Apicomplexan - Sporozoa – complex life cycleDiversity among ProtozoaAmoeba•Entamoeba histolytica–Amoebic dysentery•Naegleria–primary amoebic meningoencephalitis•Acanthamoeba–contact lens contaminantFigure 12.18aAmoebae•Protozoa with no truly defined shape •Move and acquire food through the use of pseudopodia•Found in water sources throughout the world•Few cause diseaseEntamoeba histolytica•Carried asymptomatically in the digestive tracts of humans•No animal reservoir exists•Infection usually occurs by drinking water contaminated with feces that contain cysts•Trophozoites migrate to the large intestine where they multiplyEntamoeba histolytica•Three types of amebiasis can result from infection–Luminal amebiasis•Least severe form that is asymptomatic–Invasive amebic dysentery•More common form of infection•Characterized by bloody, mucus-containing stools and pain–Invasive extraintestinal amebiasis•Trophozoites carried via the bloodstream throughout the body•Maintaining clean water is important in preventionThe Course of Amoebiasis Due to Entamoeba histolyticaAcanthamoeba and Naegleria•Cause rare and usually fatal brain infections•Common inhabitants of natural waterways as well as artificial water systems•Contact lenses wearers who use tap water to wash their lenses can become infected•Acanthamoeba diseases–Infection occurs through cuts or scrapes, the conjunctiva, or through inhalation–Acanthamoeba keratitis results from conjunctival inoculation–Amebic encephalitis is the more common diseaseAcanthamoeba and Naegleria•Naegleria disease–Infection occurs when swimmers inhale contaminated water–Amoebic meningoencephalitis results when trophozoites migrate to the brain•Prevention is difficult because these organisms are environmentally hardy•Trichomonas vaginalis–no cyst stage –Trichomoniasis - STI•Giardia lamblia–intestinal malabsorption–Traveler's diarrhea, day care centers, hikersFlagellateFigure 12.17b-dGiardiaHemoflagellates–Trypanosoma•African sleeping sickness or Chagas disease•Transmitted by tsetse flies or reduviid bugs–Leishmania•leishmaniasis – “Baghdad Boil”- Desert Storm•Transmitted by sand fly vector•Complex cells with rudimentary mouth (cytostome)•Balantidium coli is the only human parasite–intestinal disease–associated with pork•Paramecium•VorticellaCiliatesFigure 12.20Ciliates•Protozoa that use cilia in their trophozoite stage•Balantidium coli is the only ciliate known to cause disease in humans•Commonly found in animal intestinal tracts•Humans become infected by consuming food or water contaminated with feces containing cysts•Trophozoites attach to the mucosal epithelium lining the intestine•B.coli infections are generally asymptomatic in healthy adultsCiliates•Balantidiasis occurs in those with poor health–Characterized by persistent diarrhea, abdominal pain, and weight loss–Dysentery results in severe infections•Presence of trophozoites is diagnostic for the disease•Prevention relies on good personal hygiene and efficient water sanitation•Characteristics:–Nonmotile, Intracellular parasites–Complex life cycles, Asexual/sexual reproduction•Plasmodium – malaria–transmitted by Anopheles mosquito•Cryptosporidium – diarrhea; AIDS related•Toxoplasma – toxoplasmosis; AIDS relatedApicomplexans (Sporozoa)PlasmodiumFigure 12.19Infected mosquito bites human; sporozoites migrate through bloodstream to liver of humanSporozoites undergo schizogony in liver cell; merozoites are producedMerozoites released into bloodsteam from liver may infect new red blood cellsMerozoites are released when red blood cell ruptures; some merozoites infect new red blood cells, and some develop into male and female gametocytes1 2346Asexual reproductionIntermediate hostMerozoite develops into ring stage in red blood cellRingstageMerozoitesAnother mosquito bites infected human and ingests gametocytes75Ring stage grows and divides, producing merozoitesDefinitive hostIn mosquito’s digestive tract, gametocytes unite to form zygote8Male gametocyteFemale gametocyteZygoteSexualreproductionResulting sporozoites migrate to salivary glands of mosquito9Sporozoites in salivary glandPlasmodiumCryptosporidium parvumFigure 25.19•Waterborne•Found in cattle•Attach to intestinal lining•Cause watery diarrhea•Acid-fast Oocysts•Resistant to chlorineCryptosporidium life cycleToxoplasma gondiiEukaryotic MicrobesTable 12.1Helminths - worms•Life Stages–egg, larva, adult; complex life cycles–infective stage: egg or larva–definitive host: harbors adult stage–intermediate hosts: may be more than one•Classifications:•Nematodes - roundworms•Platyhelminthes - flatworms–Trematodes - flukes- nonsegmented –Cestodes - tapeworms- segmentedNematodes- Roundworms•Intestinal roundworms:–Ascaris (Giant intestinal roundworm)–Enterobius (Pinworm)–Necator / Ancylostoma (Hookworm)•Tissue roundworms–Trichinella spiralis - trichinosisFeatures of the Life Cycle of Roundworms•Parasites of almost all vertebrates•Have a number of