Final Parasitology

Polymorphous paradoxus

DH: Muskrat / Ducks

IH: Amphipod

Infective Stage: Cystacanth

Location: Small intestine

Plagiorhynchus Cylindraceus

DH: Passerine Birds

IH: Rolly Polly

Infective Stage: Cystacanth

Location: Small Intestine

Trypanosoma Brucei

DH: Mammal

IH: Tsetse Fly

Infective Stage to DH: Tropomastigote (stumpy)

Infective Stage to IH: Tropomastigote (metacyclic)

Location (DH): Blood, lymph & Tissue Fluid

Disease: African Sleeping Sickness

Trypanosoma Cruzi

DH: Mammals

IH: Kissing bug

Infective Stage (DH): Trypomsatigote

Infective Stage (IH): Trypomastigote (Metacyclic)

Location: Blood, lymph & Tissue Fluid

Disease: Chagas

Leishmania

DH: Mammals

IH: Sand Fly

Infective Stage (DH): Amastigote

Infective Stage (IH): Metacylic Promastigote

Location: Tissue Fluid

Disease: Leishmaniasis (Cutaneous / Visceral)

L. Tropica

Geography: West & Centeal Africa / Middle East

Disease: Cutaneous Leishmaniasis - Oriental Sore, Jericho’s Boil

Pathology: Skin Lesions / Ulcers

• Host squires some protective immunity

L. Donovani

Geography: India, China, Bangladesh

Disease: Visceral Leishmaniasis - Kala azar, bum bum fever

Pathology: Infection of spleen, liver, and lymph nodes

• Progressive wasting

• Death of 95% if untreated

L. Braziliensis

Geography: South & Central America

Disease: Cutaneous Leishmaniasis - Espundia Uta

Pathology: Mucocutaneous

• Degrades cartilage in nasal and buccal muscosa

• Develop before or after 30 yrs of initial infection

• Relapse if untreated

• Utilizes reservoir hosts: Sloths

Giardia Lamblia

DH: Humans

Reservoir Host: Beavers

Infective Host: Mature Cyst

Location: Small Intestine

Disease: Giardiasis

Entamoeba Histolytica

DH: Humans

Infective Stage: Metacyst

Location: Crypts of large intestine

Disease: Amoebic Dysentary

Monocystis lumbrici

DH: Earthworms

Infective Stage: Oocyst w/ sporozoites

Location: Seminal Vesicle

Gregarina Cuneata

DH: Mealworm

Infective Stage: Oocyst w/ sporozoite

Location: Intestine

Cryptosporidia Parrum

DH: Humans

Infective stage: Sporulated oocyst

Location: Gut

Eimeria tenella

DH: Chickens

Infective Stage: Sporulated oocyst

Location: Epithelium ceca

Disease: Coccidiosis

Toxoplasma gondii

DH: Cats

Infective Stage: Sporulated Oocyst

Location: Gut epithelial

Disease: Toxoplasmosis

Plasmodium

DH: Humans

IH: Mosquitos

Infective Stage (DH): merzoites

Infective Stage (IH): sporozoites

Balantidium coli

DH: Humans

Reservoir Host: Swine

Location: Small Intestine

Common Name for Acanthocephala

Thorny Headed Worms

General Life Stages for Acanthocephala

egg - acanthor - acanthella - cystacanth - adult

Kinetoplast

DNA containing regions of mitochondria located near flagella base

Glycosome

Membrane bound organelles house all enzymes for glycolysis

Life Cycle Stages for Trypanisomitida

Amastigote - Epimastigote - Promastigote - Trypomastigote

Routes of Transmission for Trypanosoma

Salivary (Anterior Station Development) - AFRICA or

Stercorian (Posterior Station Development) - AMERICA

Types of African Trypanosomes

T. Brucei - West & Central

T. Brucei Rhodensiense - Central & East

Metacyclic vs Procylic LC Stage for Trypanosoma

Metacyclic: Non - dividing stage infective to DH

Procyclic: Diving form

Stumpy form: T. Brucei

Non-dividing

African Sleeping Sickness

Cause by Nervous system evasion; 3-4 wks post infection

Immune response caused by slender form

• Chancre: Sore @ site of infection (1-2 wks)

• Winterbittom: Swelling and congestion in lymphatic system

T. Cruzi Transmission and LC

Stercorian - Fecal route

Parasitophorus Vacuole: Cellular vacuole that contains parasite; fuses w/ lysosomes

Reticular Strain: Infects Macrophages

Myotrophic Strain: Infects muscles

Chagas

Chagoma: Localized redness & swelling @ site of infection and closest lymph node

Romamas sign: Eyelid swelling

Pseudocyst: Congregation of amastigotes in muscle

Leishmania Transmission

All injected (Salivary) or regurgitated (Esophagus)

Haptomonad Parasite Sphere

Leishmania

• Modified promastigote attached to stromodeal valve in foregut where it secretes PSG

• Increases rate of reguritation

Leishmania LC

• Blood Meals: 5-6 days can cause metacyclic promastigote to reattach and transform to replicating form

• PSG: together w/ non infective promastigote will form a gel that obstructs region of stromodeal valve

Leishmania Immune Evasion

• Intracellular

• Changes in surface coat

  • Procyclic- 7nm / Inhibit complement system and fomration of P. Vac

  • Metacyclic- >17 nm

  • Amastigote- almost absent

Immune evasion Giardia

• Cyst shed before host has time to mount an effective response

• Infection resolved in 2 weeks w/o treatment

Pathology of Giardiasis

Attachment of trophozoite in small intestine

Axostyle

Stout median rod serving as a support structure

Trichomonads LC

Contains flagella, axostyle, and undulating membrane

• Direct transmission

• Trophozoites are only stage

• Replication via BF

T. Vaginalis

Repro in humans

Via sexual contract or w/ soiled clothing

Pathology: Trichomoniasis

T. Gallinae

Respiratory tract of birds

Horizontal transmission - Sharing contaminated water

Pathology: relatively asymptomatic but can lead to sudden death within 4-18 days

T. tenax

Mouth of Humans

Pathology of Entamoeba histolytica

Amoebic Dysentary:

• trophozoites, precysts, cysts found in loose/partial stool

• Destruction of epithelial cells which leads to formation of ulcers

• precyst formation will not form in not in large intestin

Apicomplexans: Conoid

Coiled microtubles that exist as fibrillar cones inside polar ring

Apicomplexans: Polar Ring

Rings of microtubules that support rest of apical complex

Apicomplexans: Rhoptries

Tubular or saccular organelles used in secretion

Apicomplexans: Micronemes

elongated tubular organelles used in secretion

Eugregarina: Syzygy

Pairing of gamonts

Eugregarina: Gametocyst

Paired gamonts enveloped in cysts

Eugregarina: Ansinogametes

Indistinguishable gametes

Eugregarina: Protomerite

Anterior portion of a gamont

Eugregarina: Dentomerite

Posterior portion of gamont

Eugregarina: Primite

Anterior gamont of a syzygois pair

Eugregarina: Sattelite

Posterioir gamont of a syzygous pair

Eugregarina: Epimerite

Small, conical structure on gamont that is inserted into host intestinal epithelial

Eugregarina: Dihiscence

Extrusion of oocyst through tubes or long chains

Toxoplasma: Endodygeny

Production of 2 daughter cells that “bud” internally

2 LC Stages of Toxoplasma

Enteroepithelial: replication occurs in intestinal epithelial

Extraintestinal: Replication outside of intestinal epithelial

Toxoplasma: Tachyzoites

Fast diving schizonts

Toxoplasma: Bradyzoites

Slow dividing Schizonts

Toxoplasma: Zoitocyst

Tissue cysts containing bradyzoites

Toxoplasmosis Pathology

Acute infections

• Painful, swollen lymph nodes & fever - Can develop chronic infections

  Symptoms depend on cyst location

  • Brain: Chronic encephalitis

  • Eye: Blind spots

  • Heart: Heart damage

• Congenital Toxoplasmosis: Vertical transmission

Toxoplasma: Premunition

Protection against super infection

Plasmodium Key LC Points

• 1st step is to invade liver cells in DH

• 2nd step is to initial Erythrocytic

  • synchronous release of merozoites cause pathology

  • Recrudescence: Initiation of clinical disease resulting from activation of schizonts. merozoites in RBC

Plasmodium: 2 LC Stages

Erythrocytic: RBC are infected

• Hemozoin: insoluble polymer of heme produced during hemoglobin metabolism

Exoerythrocytic: Cells other than RBC

• Hypnozoites: Dormant stage of sporozoite in live and responsible for relapse

Pathology of Plasmodium

RBC Destruction - Severe anemia

Blackwater fever: Renal failure

B. Coli

Macronucleus: reproduction

Macronucleus: Metabolism

Taenia Solium Common Name

Pork Tapeworm

Hymenolepis nana Common Name

Dwarf Tapeworm

Taenia Saginata Common Name

Beef Tapeworm

Diphyllobothrium Common Name

Broad Fish tapeworm

Taenia pisiformes common name

Rabbit tapeworm

Dipylidium canium Common name

dog tapeworm

What are the functions of the synctial tegument (tapeworms)

absorption, protection, digestion

What are the larval stages present in Schistosoma?

Sporocysts, cercariae, miracidium

What type of scolex does taenia sp have?

Acetabular

What is the DH of dicrocoelium dendriticum

Sheep

Which tapeworm sp is capable of autoinfection?

Hymenolepis

How do humans become infected with Schistosoma sp?

Cercaria penetrate the skin

What is the larval stage of Aspidobothreans?

Cotylocidium

Which sp. causes liver rot in sheep?

Fasciola hepatica

Which sp can you get cysicercosis from

Taenia

What disease do you get from avaian schistoma

Swimmers itch

Chonorchis sinensis common name

Chinese liver fluke

Fasciola hepatica commons name

Giant liver fluke

What is not part of the aquatic lifecycle of a tapeworm

Cysticeroid

What part of the schistosoma life cycle causes the most pathology

eggs

What is theinfective stage of Dipylidium canium

cystercercoid

How do humans become infected with Echinococcus sp.

Consuming eggs from a pet

Which following sp of tapewomrs fo not do apolysis

Diphyllobothrium

Where does fertilization occur in Digeneans

ootype

Which sp of schistosoma is found in the large intestine

S. mansoni

where do fasciola hepatica adults reside in the DH

bile ducts

What is the infeective stage of Echinococcus

hydatid cyst

How long does it take for P westermani to mature?

8-12 weeks

Which sp can you get pernicious anemia from

diphyllobothrium

Which can have guinea pigs as paratenic host

paragonimus

What are the 3 types of tapeworm scolex

acetabular: Rostetllum & Sucker

Bothria: Groove “Shallow and elongated”

Bothridia: Leaf like

Which species has a dauer larva

Steinernerma sp

What is DH for mermis nigrscens

grasshopper

Which trichinella sp is found in polar bears

t. nativa

Which J stage is found in nurse cell

j1