What are parasites
Organisms that obtain food and shelter by living on or within another orgnaism
What are examples of internal parasites
Protozoa, Helminths
What is a host
Organism that carries the parasite
Vector
organism that is responsible for transmitting the parasitic infection
T/F: There are no vaccines for any parasitic infections
True
What are protozoa
Single-celled eukaryotes
What are the three type of protozoa that can be involved in infectious disease
intestional, luminal, and blood
How are intestinal protozoa transmitted
Oral/Fecal route
What is the life cycle of intestinal protozoa
Cyst (spore) is dormant when swallowed, it goes through excystation to become a trophozoite, once it is a trophozoite the organism with move to the intestines and grow to cause symptoms while also going through enzycystation to become a cyst for survival
What is the etiologic agent for amebiasis
Entamoeba histolytica
What is the life cycle for entamoeba histolytica (amebiasis)
Ingestion of mature cysts of E. histolytica, excystation in the small intestine to release trophozoites, trophozoites migrate to the large intestine
What are symptoms of acute amebiasis, what organs are involved
abdominal pain, frequent bloody dystentery with necrotic mucosa, low fever/ small and large intestine
What are symptoms of chronic amebiasis, what organs are involved
Recurrent bloody and mucoid dysentery with intervening constipation/ small and large intestine, liver, lungs, brain
T/F: Acute and chronic amebiasis can be associated with abscesses, hepatitis, pneumonia, encephalitis
False: Only chronic amebiasis is associated with abscesses, hepatitis, pneumonia, and encephalitis
What are the drugs that will treat amebiasis
Iodoquinol, metronidazol
T/F: Better hygiene and efficient sewage treatment and disposal can prevent amebiasis
True
What is the etiologic agent for Giardiasis, how is usually distributed
Giardia lambia (a flagellate), drinking from contaminated streams (waterborne)
What is the life cycle of Giardia lambliasis (girdiasis)
Cysts excystation in the small intestine, the trophozoites multiply by longitudinal binary fission, encystation occurs during transit to the colon
What is the resirvoir host of giardiasis, vector
Beavers, water
What are the symptoms of acute giardiasis, organs involved
abdominal pain, frequent diarrhea
What are symptoms of chronic giardiasis, organs involved
abdominal paint, frequent diarrhea, malabsorption, lactose intolerance/ small and large intestine
What is the key difference between giardiasis and amebiasis
Giardiasis does not have mucus or blood in stool, no fever, and it doesn’t have symptoms that involve other organs
What is the treatment for giardiasis
Iodoquinol and Metronidazol
What is the most common luminal protozoa, what is the etiologic agent
Trichomoniasis, Trichomonas vaginallis
Why can trichomoniasis survive with becoming a cyst
It will not enter the GI tract
Where does the trophozoit of trichomoniasis reside
Vagina or prostatic secretions and urine
What are symptoms of trichomoniasis in women, men
mild to severe vaginitis in heavy infections, fowl smelling discharge/ occasionally mild urethritis and/or prostatitis
What are key complications associated with trichomoniasis
Increase a women’s succeptibility to HIV, increased chance HIV is passed, preganant women at risk of premature or low-birth weight babies
How can trichomoniasis be prevented, what are the treatment options
Condoms/ Vinegar douche (reduce pH) and Metronidazol
T/F: Trichomoniasis does not have cysts or vectors
True
What types of hosts are beavers of giardiasis
Reservoir hosts
What is a blood protoza that has a life cycle that occurs in cats and small rodents, what is the etiologic agent
Toxoplasmosis, Toxoplasma gondii
What is the way that humans can become infected and cats become infected as well
Eat raw meat
What is the life cycle of toxoplasmosis in cats
Decystation in the small intesting, development of micro (male) and macro (female) gametocytes, fertilized macro gametocytes become oocyts that are dischagred into the gut lumen and excreted
What is the life cycle of toxoplasmosis in humans
Sporozoites relased from the ococyst in the small intestine penetrate the intestnal mucosa into macrophages where they divide very rapidly and form a cyst, infected cells bust and release tachyzoites enter other cells where they are protected from the immune system
T/F: Toxoplasmosis is rarely symptomatic but does have serious consequencs for pregantnt women and immunodeficient hosts
True
What can happen toxoplasmosis patients who are immucompromised, pregnant
generealized parasitemia involving vital organs/ miscarrige, mental retardation, active retino-chorditis
What are the drugs used to treat toxoplasmosis
Pyrimtehamine, sulphadiazine, spiramycin
T/F: Pregnant women infected with toxoplasmosis can be given spiramycin, while unborn children with toxoplasmosis can recieve pyrimethamine and sulfadiazine under severe circumstances
True
What is the role of farm animals, cats, and mice in toxoplasmosis transmission
vectors and reservoir hosts, vectors, reservoir hosts
What are helminths, what is the most common helminth, what is the most common etilogic agent
Parasitic worms, elephantisiasis, wuchereria bancroft
T/F: The vector for Helminths are mosquitos and there is no reservoir host
True
Where does the elephntisiasis grow
Lymphatics
How long can the asymptomatic phase last
10 years
What symptoms are seen in the obstructive (chronic phase)
Thickening of the skin and gradually developing elephantiasis
What is used to treat elephantisiasis
Ivermectin, An actinomycete derived 16-membered macrocyclic lactone
T/F: The adult form of Wuchereria bancrofti is microscopic
False: up to 10 cm in length