Phoresis: symbiosis in which one organism is carried around by its host phoretic transfer -Ex: Bot flies

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Dorothy Holland
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1 BIOS385 CLASS NOTES; JBM-SPRING Book: Foundations of Parasitology 9 th Edition lamarck.unl.edu/parasitology-unl/ 13/I/2016 Lamarck: first person to develop a full theory of evolution (before Darwin*) inheritance of characters -was wrong Alfred Russel Wallace: was scooped by Darwin -sent Darwin message that proposed Natural Selection -Zoogeographic region: -Holarctic: Nearctic (New World), Palearctic (Old World: Europa and Asia) -Neotropic; Ethiopian or Afrotropical, Oceania, Oriental (Malagasy, Indo-Malaysian) Ross: figured out life cycle of malaria Parasitism: an intimate symbiotic association parasite lives closely with host and causes the host some degree/level of harm Symbiosis: living together (2 different species) Phoresis: symbiosis in which one organism is carried around by its host phoretic transfer -Ex: Bot flies Mutualism: symbiosis where both partners benefit -Ex: Termites, ruminants Commensalism: symbiosis where one organism benefits but does not benefit/harm their host Ectoparasite: outside of host infests host Endoparasite: inside of host infects host Obligatory parasite: must parasitize host in order to survive -cannot live without host Facultative parasite: can be free-living or can parasitize -Ex: Neglaria falleri amoeba that kills people if they are inhaled (dirty water in TX) Accidental parasitism: parasites transferring to wrong host -Ex: animal consumes an infected host; cross-contamination Temporary parasite: micro-predator Hyper-parasite: parasite that parasitizes another parasite -protozoan of nematode that causes blackhead in chickens and turkeys (Histomonus meleagris) Bot Fly: cutaneous parasite ; endo-ecto parasite Parasitoid: intermediate between parasite/predator; only kills one host (single event) -Ex: Hymenopterans (wasp lays egg in arthropod)

2 Definitive host: where sexual reproduction occurs Intermediate host: where asexual reproduction occurs -amplification stage of life cycle Paratenic host: transport host -no development occurs but maintains infection -Ex: copepods Reservoir host: parasite population maintained in a population of animals Zoonosis: disease of wild animals that can be transferred to humans 15/I/2016 Ticks: Hypostome exposed Mites: Hypostome not exposed Example of zoonosis: Echinococcus spp. Fox Vole Fox (or Fox Human--asexual reproduction) -West Nile Virus in wild bird populations Epidemiology Vector: transfers infection/disease (parasite); transfers parasites between/among hosts -no amplification of parasite within the vector direct transfer -Ex: ticks, mosquitos, water, Stomoxys spp. (face flies of cows) Direct life cycle: use only one host to complete life cycle -monozenous: using a single host Indirect life cycle: use more than one host to complete life cycle -heterozenous: using more than one host (all trematodes) Sylvatic life cycle: in sylvatic areas without/not among people; lifecycle in natural settings Domestic life cycle: in domestic areas that include people/people s influence Parasitology: study of parasites and parasitism Good book: Bjorn Kurten, Dance of the Tiger and Single Tusk -interactions of Homo sapiens and Homo neandertalensis Trichenilla spiralis-nemas that end up encysting in tongue/abdomen and kills humans Taxonomy: the science of scientific naming of biological entities -established by Linnaeus (1758, Sistema naturae)

3 Binomial nomenclature: method of naming -Kingdom; Phylum; Class; Order; Family; Genus; Species Systematics: science of understanding evolutionary relationships between/among organisms over time G. G. Thompson: Splendid Isolation Alexander Von Humboldt (1848): thought that the continents once fit together Alfred Wagoner (1913): proposed continental drift -Pangea (1 st continent) Laurasia (North); Gondwanaland (South) Top of Everest: limestone with fossils on top 20/I/2016 Investigating parasitology: Guiding principles: 1.) Must use phylogenetic trees (not sufficient*) 2.) We must be responsible for well-formulated questions as scientists 3.) We are responsible for the quality of data used 4.) Formulate new questions to further scientific investigation Parasitology: when people first discovered symptoms of parasitic infection -Ex: Eskimos would eat bot fly larvae from the backs of caribou (had names) -Ex: New Guinea-had common names for birds -Binomial nomenclature was necessary Alexander Von Humboldt: spontaneous generation (discounted by Louis Pasteur) 4,700 years ago: Chinese knew that nematodes were transferred by eating rotting meat Ecological classification: FW fish vs. SW fish Teleological classification: edible vs. inedible; domestic vs. wild; etc. *No rule set in naming above family level of classification Phylum: Protozoa/Protista/Proctista: - one cell does it all -Ex: Termite protists produce cellulase to breakdown cellulose Class: Kinetoplastida -Hosts/Parasites: Intermediate host; definitive host; reservoir host; vectors Family: Trypanosomatidae -two groups of trypanosomes: (ecological classification) 1.) Salivarian: develop in the anterior end of arthropod host and are transmitted to vertebrate host via bite; African forms of Trypanosoma spp. (mostly Old World) 2.) Stercorarian: develop in the posterior end of arthropod host and are transmitted via a fecal deposit if infective stages; South American forms of Trypanosoma spp. (mostly New World)

4 (Pg. 66) Tsetse flies (Glossina spp.) occur in Central Africa aka Fly belt -Trypanosomiasis aka African Sleeping Sickness -Bruce: worked on problem of African Sleeping Sickness with Koch (Koch--first person to figure out phathenogenicity of bacteria parasites Typhoid fever*) -Bruce set up rigorous methods to figure out the transfer of trypanosomes from flies to animals and then to domestic animals then humans (Trypanosoma brucei) Moved horses/cows at night to fly-infested areas because flies don t bite at night -Nagana: domestic animals that are infected with trypanosomes (Nagana= Zuli word for useless/no good ) -Bruce ruled out that plants/feed were the cause; found out that/made correlation that flies were transferring trypanosomes; found them in the blood of domestic animals (Nagana); killed domestic animals -Tsetse flies (Glossina spp.): to control these flies cut down all plants/trees to eliminate Tsetse flies; created a wasteland Based on making $ by grazing cattle and exploiting the land; killed every large mammal in an entire 250mi 2 area to control/eliminate all reservoir hosts 22/I/2016 Tsetse flies (Glossina spp.): Nagana of animals; white man helped spread the Tsetse flies via colonization of Africa Two types (sub-species) of trypanosomes in Africa: 1.) Trypanosoma brucei gambiense -most common in West and Central Africa; causes sleeping sickness -Chronic form (Kills you within a few years) 2.) Trypanosoma brucei rhodesiense -most common in East and Central Africa -Acute form (Kills you within a few months) -Reservoir hosts: large mammals Other species: 3.) Trypanosoma brucei brucei (causes Nagana) 4.) Trypanosoma congolense (causes Nagana) 5.) Trypanosoma vivax (causes Nagana) 6.) Trypanosoma evansi -widespread; moved around by people; transmitted via horseflies (Tabanidae); affects domestic animals Nagana 7.) Trypanosoma equinum (South American; affects horses) 8.) Trypanosoma equiperdum (Venereal disease in horses Dourine) *V.A.T. (Variable Antigen Types) of trypanosomes in rats (T. lewisi) Pg *Morphology: Pg

5 25/I/2016 Class: Kinetoplastida Parasites and vectors -Trypanosoma livingstoni: a new species from African bats; supports the bat seeding hypothesis for the origin of Trypanosoma cruzi in South America *Trypanosoma cruzi: Carlos Chagas (Pg. 72) How to diagnose Chagas? 1.) Xenodiagnosis: let different species of Triatoma spp. grown in cultured/sterile conditions feed on you, wait ~10 days, squish bugs, look for trypanosomes effective way to diagnose trypanosomiasis 2.) ELISA 3.) PCR CENTROP: Belgians, Santa Cruz de la Sierra W.H.O.-- $200 million into Rolling Back Chagas Reservoir hosts: mammals; bats, mice and rats (endemic), Xinarthrans (sloths, armadillos, ant-eaters), Marsupials, Carnivores Peridomestic (infectious disease) life cycle: [dogs, bats, rats] humans -occurs around human habitations (houses; human associated) - Vinchugas (Bolivian term) aka Triatoma spp. bugs; live in the thatched roof of houses Sylvatic cycle: in the woods; where there are no people (wild lands) General: Trypanosomes -occur in fish, reptiles, birds, mammals, amphibians -have no intermediate host, only vector because there is no asexual/sexual form in life cycle -splenomegaly (enlarged spleen) -megacolon (archaeoparasitological evidence) -how to treat? 1.) Chronic form: can treat over time; still kills host 2.) Acute form: kills host quickly DON T EAT BUGS 27/I/2016 Triatoma spp. + Trypanosoma spp. life cycle - Chagoma : selling that occurs on face; connective tissue swelling (amastigotes released in blood) Phylum: Protozoa Class: Kinetoplastida -two major types of transmission routes for Leishmania spp. (Pg. 80)* 1.) Blood transfusion 2.) Sand fly: vector -Old World: Phlebotomus sp. -New World: Lutzomia sp.

6 -lots of genetic diversity (more than expected) -can be treated with antimonial compounds applied on lesions or injected intravenously or intramuscularly secondary infections can be treated with antibiotics -Immuno-privileged sites: inside a cell; inside eyeball Old World: (vector: Phlebotomus sp. sand fly Palearctic, Ethiopian) -Leishmania tropica and L. major cause cutaneous leishmaniasis ulcers in skin -heals in 2-12 months -low numerical density in skin/body -Distribution: West Central Africa, Middle East, South West Asia, India -Diagnosis: find L-D bodies (L. donovani bodies) from a smear of the legion stained in geimsa New World: (vector: Lutzomia sp. sand fly Neotropical/Nearctic) -Leishmania braziliensis causes muco-cutaneous leishmaniasis -Sylvatic -Distribution: from Central Mexico hasta Argentina (East slopes of Andes) -L. mexicana -Distribution: Texas, Dominican Republic, Mexico, Central America -Cutaneous lesion -L-D Bodies, ELISA (detections) -ulcer appears after a few weeks and may take long period of time to heal 29/I/2016 Leishmania donovani: Old and New World in tropical areas (poverty-stricken areas) -diagnosis: ELISA or immunofluorescent antribody (I.F.A.) - transmission dynamics of leishmaniasis in the Sudan (article) Amoebas and Flagellates -Flagellates: two types 1.) Blood and Tissue 2.) Intestinal and Genital Amoebas: -Entamoeba histolytica Morphology and Diagnosis -cysts have 4 nuclei* -trophozoites: feeding/active stage of organism; clean cytoplasm (not foamy ) -find cysts and trophozoites in loose stool -find only cysts in hard stool -Small intestine: trophozoite encysts (more water) -in-between SI and LI: find uni-nucleated/bi-nucleated cysts (immature cysts) -Large intestine: mature cysts with 4 nuclei (less water) -Cysts: are susceptible to heat and hard freezes -are spherical, can stay in environment for up to one month with adequate moisture

7 -Trophozoites: consume mucosa and starches of intestinal tract (active stage); damage gut (epithelial lining; gut produces more mucosa) -Problems: Pathology damage; Symptoms body s signals/reactions from the pathology Entamoeba histolytica: has surface enzymes that digest/hydrolyze host epithelial lining/cells -causes flask-shaped ulcers in epithelial lining -Pathology: -Primary: intestinal lesions, mostly in descending colon -Secondary: infections of liver, lungs, spleen, pericardial lining, genitals, skin, eyes -goes through hepatic portal vein from gut to liver and then dispersed throughout body -Incubation period is ~4-5 days (time from initial infection to first symptoms) -Symptoms: -dysentery; diarrhea with blood -rectal tenesmus: feels like you have to poop ; watery stool -10% of world s population is infected; only 3% have symptoms -lots of carriers without symptoms (asymptomatic) -dangerous because it is infectious for one month -Distribution: world-wide - wherever there s poop and people; it s possible - <1% in Canada and USA - >40% in tropical areas -Flagel: three rounds of tetracycline -Prognosis: 90% chance of recovery; can cause permanent chronic bowel problems -Vectors: contaminated food, water, medical treatment; fertilizing with night soil -Eccentric nuclei (not in center) 1/II/2016 Triatoma spp. vectors for Trypanosoma cruzi and T. lewisi (Stercorarians; blood flagellates) -not equal vectors: vector competence -more exposure than infection=higher vector competence -differ in size of bloodmeal -Triatoma infestans: largest bloodmeal (higher level of vector competence) -Triatoma sordida: smallest bloodmeal (lower level of vector competence) -Hemimetabolous life cycle: no change in morphology from larva adult (egg N 1 N 5 adult) -Holometabolous life cycle: adults look different from larva (caterpillar butterfly) Genus: Iodamoeba -Iodamoeba buetschlii: only species that infects humans, other primates, and pigs -not as pathogenic as Entamoeba histolytica -sign of water contamination -has a large glycogen vacuole Order: Diplomonadida (Pg. 88) Family: Hexamitidae -endo-commensual (not pathogenic)

8 -divides by binary fission -morphology and life cycle stages (Pg. 89) -Genus: Giardia -Giardia duodenalis: most common flagellate of the human G.I. tract -start to encyst when they are starved of cholesterol -causes malabsorption/villi blockage of G.I. tract Trichomonas vaginalis (Pg ) -cosmopolitan (where people are) -personal hygiene plays a large role in transmission -vaginitis (inflammation) -males: discolored discharge; in urethra, seminal vesicles, prostate -females: strawberry cervix (disintegration of vaginal lining) pH in vagina; T. vaginalis raises ph to 5.5+ (better environment for a bloom) -can cause spontaneous abortions/still births; female morbidity (inflamed cervix won t dilate) -vectors: soiled linens/washcloths; sexually transmitted -reproduction: binary fission 3/II/2016 Apicomplexans: Gregarines (with thermite plasmid=apical complex) -Cyclosporidium parvum: infects/harms bovines (vacas); causes diarrhea -Milwaukee WI: 403,000 cases off crypto out of 1.6 million in 1995 epidemic (almost 1/3 of population) -Toxoplasma gondii: obligate intracellular protozoan parasite -anything warm blooded and mammal can be a possible host -congenital/cervical transmission (from mama to unborn child) can cause hydrocephalus from toxoplasmosis -infective stage has an apical complex with micromeres -manipulation hypothesis: less adverse to felids (definitive hosts of parasite) Malaria: -Family: Apicomplexa -Genus: Plasmodium -P. vivax (needs immature erythrocytes) -Hypnozotic (hide out in liver): 1.) P. falciparum (worst one to get) 2.) P. ovale 3.) P. malariae -causes cyclic fever with splenomegaly -get fever with malaria when erythrocytes burst -Hypnozoites: hide out/stay in liver and are responsible for recurring symptoms/fevers only: Plasmodium falciparum and P. malariae *Anopholes spp. mosquitos are vectors Sporozoites merozoites early/late trophozoites schizonts infect erythrocytes asexual reproduction 5/II/2016

9 (Malaria continued) Anopholes spp. (mosquitos; definitive host) -females bite (Pg. 145)* Sickle-cell anemia: immune to malaria (Plasmodium falciparum) -erythrocytes poor in transporting O 2 -shortened life-span -heterozygous humans maintain the trait (can reach reproductive stage) -Duffy blood-type: high resistance to malaria Mason and Ross: won the Nobel Prize working with Culex sp. -they proposed that Plasmodium spp. were the causative agent in malaria Ades egypti: yellow fever mosquito; nests in tree holes/bromeliads/tires/cans etc. 8/II/2016 Histomonas meleagridis: -Venereal disease of nematodes affects their hosts; Order: Galliformes (turkeys and chickens) -flagellated; protistan/protozoan -distribution: world wide within all galliforms (cosmopolitan) -causes blackhead in turkeys* Phylum: Microsporidia Family: Nosemidae (Apidae honey bees) -Encephalitozoan cuniculi vertebrates -E. bienuesi birds/mammals Myxozoa: probably related to Cnidarians (Pg. 180 life cycle) Family: Myxobolidae -morphologically similar to a nematocyst; functions like a nematocyst where it punctures and injects DNA into host cell -Myxobolus spp. -Host: Salmonidae; causes whirling disease Phylum: Mesozoa (parasites of marine invertebrates: Mollusca and Echinoderms) Degenerate organisms?? -Class: Dicyemida; parasitize cephalopods (kidneys) -Class: Orthonectida; parasitize echinoderms, mollusks -Orthogenesis: assumes evolution -orthogenetic evolution, Teleological (ultimate goal driven 4 phylogenetic hypotheses Speciation: species give rise to species 10/II/2016 Primary literature: published anuk puk -Ex: Parasites and Vectors (journal) Eucestoda: true cestodes Bilateria: all organisms that are bilaterally symmetrical

10 Ancestral vs. derived characters primitive vs. advanced Phylum: Platyhelminthes (platy=flat; helminthes=worm) 1.) Dorsoventrally flattened 2.) Usually with limited digestive system (cestodes) 3.) Size range: <1mm to >60m (whale flat worms) 4.) Bilaterally symmetrical 5.) Ciliated epithelial tissue (at least in larvae) 6.) Cephalized (ladder-type nervous system) 7.) Osmoregulatory system aka excretory system -Protonephridia=flame cells Phylum: Platyhelminthes (dorsoventrally flattened) Class: Trematoda -posterior adhesive organ (Acetabulum or ventral sucker) -Adults: have an anterior sucker followed by a pharynx -No anus but have a branched cecae -Subclass: Aspidobothria (have posterior sucker with compartments) -Subclass: Digenea (almost as diverse as nematodes) -more than one host necessary to complete lifecycle (2+) -first larval stage: miracidium (ciliated, has eyespots) one miracidium can produce 50,000+ circariae -second larval stage: sporocyst (daughter sporocyst produce rediae which produce circariae) 15/II/2016 Trematode egg production * Fasciola hepatica life cycle (Pg. 257) -Humans can get it from chewing reeds (Lake Titicaca) Yungasicola travassosi life cycle * Alaria Americana life cycle (Pg. 237) Ectolesaphil (?) eggs: yolk comes from external source (vitelline gland)

Parasitic Protozoa, Helminths, and Arthropod Vectors

PowerPoint Lecture Slides for MICROBIOLOGY ROBERT W. BAUMAN Chapter 23 Parasitic Protozoa, Helminths, and Arthropod Vectors Parasitic Diseases Protozoan and helminthic parasites are emerging as serious