Parasites

Question 1

• Parasite def?
• Protozoa?
• Metazoa?
• WHO Mortality rates: Infections disease kills what percent of people? Percent of this parasites?
• Life cycle: Complex? How many hosts? Definitive host? Intermediate host? Replicate sexually? Protozoa usually reproduce where? Most metazoa worms? Tropism essential for? Many have mechanisms to avoid? Why are there few vaccines/drugs?
• 3 worm types?
• 5 protazoa types?

Answer 1

• Organism that lives on or within another living organism at whose expense it gains an advantage
• unicellular eukaryotes
• multicellular eukaryotes (worms/insects)
• One third; 22% parasites
• yes; >/= 1; Sexual reproduction pccurs; no sexual reproduction; sometimes; Humans; Do not replicate in humans but develop there; parasites; immune response; eukaryotic so similar targets
• Round worms, flat worms, tape worms
• Ameobas, flagellates, ciliates, sporozoa, microsporidia

Question 2

• Schistosomiasis: Released in? Then? Then penetrate? What are released to swim? Next? (2) Migrate to where? Via? To do what? Paired adults then go to?
• Subtype location: S. mansoni? S japonicum? S haeotobium?
• Clinical phases: 1.) Cercavial invasion? Lasts?
  2. ) Worm maturation: Acute schistomiasis? Signs? How long after invasion?
  3. ) Eggs in tissue: Liver? Bladder (S haem)?
• Control strategies? (3)
• Drug for blood, intestinal, lung, hepatic fluke?
• Drug for F. Hepatica, F. gigantica?

Answer 2

• Urine/feces; eggs hatch; snails; Carcariae; penetrate skin/ lose tail; liver via portal blood to develop; bowel/rectum to lay eggs
• Feces, feces, urine
• Dermatitis (swimmers itch); 2-3 days;
• Serum sickness; lympahonopathy/splenomegaly; 4-8 weeks
• Chronic granulomas/fibrosis; same
• Avoid infected water, anti-schistisome (praziquantal) drugs, mulluscosides to kill snail hosts
• Praziquantal
• Triclabendazole

Question 3

• Malaria: Type of organism? Endemic where? (4)
• Drug treatment? Sensitive area? Resistant?
• Life cycle: Type of mosquito carrying malaria? Injects what parasite? Travels where? What grow and divide? How long? Produce thousands of? Some stay? Next? Replicate how? And release what how often? Some leave asexual cycle and? Mosquito ingests? Develop into what, where? Gamete to? Then? Then?
• Can lead to what symptoms? (3)
• Erythroctye changes with Falcipirum malaria?
• Acquired immunity? Vaccines?
• Genetic resistance to F. Malaria? (3)

Answer 3

• Protozoa; Africa, Middle East, Asia, S. Pacific
• Chloroquine; South S. America, North S. Amer.
• Anapholes; sporozoites; liver by blood; sporozoites, 5-16 days, haploid merozoites; dormant in liver cells; meterozites enter blood and invade RBC’s; Asexually; release meterozoites into blood every 1-3 days; turn into sexual gametes; gametocytes; gametes in mosquito gut; zygote; oskinete; sporozoites
• Anemia, hypoxia, fever every 3 days
• Knobs develop via adhesive protein PFEMP1 which helps attach to caps/venules; sequestered
• Prevents high level of disease but does not eradicate infection (premunition); can be lost; no
• Sickle cell, thal, ovalocytosis