Parasitology 1st exam

• What is the difference between innate and acquired immunity?

  * innate is present at birth & non-specific.

  * acquired is specific for a given disease organism & it requires exposure to the disease.
• Name a specific antigen-linked cell mediated response.

  * lymphocyte (B-cells, T-cells) activation

  * macrophage/killer cell response to tagged cells (detection of antigens & infection)
• Name a vector for Trypanosomes.

  * tsetse flies

  * kissing/reduviid bugs

  * sand flies
• What is the function of antibodies?

  * specific antigen-binding

  * binding to foreign bodies/cell recognition for defense
• Name a tissue that trypanosomes could be found in.

  * blood

  * muscle

  * liver, spleen
• What are the benefits of antigenic variation for a parasite?

  * avoidance of the immune response

  * time to multiply/increase infection

  *Parasite remains undetected in host's body
• During infection, why does the morphology of a trypanosome matter?

  * connected to movement in fluids (blood, lymph)

  * connected to organs or tissues that the trypanosome might be found in
• Why is an adaptive immune response advantageous to parasites?

  * time required to generate the immune response

  * ability to avoid the response because of the time lag (antigenic variation)

  * Time to duplicate & spread
• What are two different diseases one could get from trypanosomes?

  * African sleeping sickness- Trypanosoma brucei spp.

  * Chagas disease- Trypanosoma cruzi

  * Leishmaniasis- Leishmania genus..
• What is a disadvantage of the immune system in terms of immunity against parasites (or viruses, etc.)?

  * time required to make antibodies (~14 days for immune system to respond to antigens!)

  * antigenic variation (in parasites)- evolve & adaptations
• What form of trypanosome is usually found in blood?

  > Trypomastigotes (largest, final form, sail or veil connections throughout the body to the flagella!)
• What ability do trypanosomes have to avoid a good immune response?

  ~ antigenic variation
• Forms of Kinetoplastids:

  1. Amastigote
  2. Paramastigote
  3. Promastigote
  4. Epimastigote
  5. Trypomastigote

  
• Histozoic VS Coelozoic ?

  ~Histozoic is in Tissue

  ~Coelozoic is in Cavities
• Obligate parasite VS Facultative parasite?

  ~Obligate MUST be in a host

  ~Facultative has free living phases in their life cycles

  
  

  E.G. Giardia water- cyst/spore phase, flagellated & deflagellated phase inside body
• Permanent VS Intermittent/temporary ?

  ~Permanent is in the life of host

  ~Intermittent is not for the entire life
• Accidental (Incidental) Parasites

  Not normally parasites, but can impact others (food on dead tissue, etc)
• Parasitoids

  Insects that parasitize other insects!!
• The different types of hosts:

  ~ Definitive: host to ADULT parasites (gives birth in host !)

  ~ Intermediate: host to IMMATURE parasite stages

  ~ Paratenic: transport Only!

  ~ Reservoir: host's parasites infective to humans (E.G. Cats and T. gongii)
• Parasite Populations

  Prevalence?

  ~Prevalence- % of one host species infected
• Parasite Populations

  Incidence?

  ~ Incidence- # of new infections per unit of time/# uninfected hosts
• Parasite Populations

  Abundance?

  ~ Abundance (density)- Average # parasites per host
• Parasite Populations

  Aggregated Populations?

  ~ Aggregated populations- most parasites in few hosts & most hosts uninfected
• Parasite Populations

  Infrapopulation?

  Infrapopulation- # of parasites of 1 species in an individual host
• Parasite Populations

  Infracommunity?

  Infracommunity- All parasites of all species in an individual host
• Epidemiology is the ecology of disease!
• Epidemiology

  • Distribution?

  ~ Nidus (focus)- ecological conditions of a disease

  E.G. No mosquitoes in the winter = no disease!
• Epidemiology

  • Transmission?

  Physical, usually via eggs

  ~ Vector biology- organism that transmits disease from/to another.
• Epidemiology

  • Landscape epidemiology?

  Landscape epidemiology- climate, plant & animal populations, geology, human activity, etc.

  > Awareness of conditions, where parasites could be picked up!
• Epidemic


  Widespread human disease
• Epizootic


  Widespread animal disease
• Zoonoses

  diseases of animals that are TRANSMISSIBLE to humans.
• Host switching

  becoming adapted to a different host
• Defense systems

  ~ Body structure, Innate & acquired Immunity, cellular & humeral immunity ~
• Skin- 15% of body weight

  Epidermis, Dermis, & Hypodermis (Subcutaneous tissue)
• Epidermis

  ~ Stratum Corneum- plate-like cells that are shed

  ~ Stratum basal layer- cell formation
• Chagoma vs Romana

  Chagoma- ring like sore opening on skin (like chancres)

  Romana- Swelling resembling a tumor that appears at the site of infection for Chagas' disease.
• What is Parasitology?

  The study of parasites & their hosts- an ecological relationship, or symbiosis.
• Endoparasites vs Ectoparasites

  Endo- Inside body

  Ecto- Outside (skin)
• Dermis

  Supports Epidermis, Contains sensory structures!