Protozoan Diseases

• Trichmonaisis
• Cryptosporidiosis
• Giardiasis
• Leishmaniasis
• Toxoplasmosis
• African Sleeping sickness

Trichomonas vaginalis (STD)

• single-celled protists
• flagellate (4 anterior, 1 posterior)
• does not survive long in external environments
• Humans are only known reservoir

Direct sexual

• intense itching
• copious green/yellow discharge
• discomfort w/ urination and sex

• about 7.4 million each year of new cases
• Highest prevalence among those with multiple sex partners or other venereal diseases

• ANtiprotists (metronizadole Flagyl)
• self-limiting in men

contributes to infertility in males, low birth weight/ preterm births, herpes simplex 2, Pelvic Inflammatory Disease (PID), HIV

Cryptosporidium parvum

• single-celled obligate intracellular parasites
• Highly infectious
• most commin cause of water borne diseases

• Cyst- resistant to most 'normal' water disinfection system (eg. chlorine)
• Sporozites- directly invade human intestinal epithelium and cause disease( millions released with bowl movements, weight loss due to frequent bowl movement)

range from mild diarrhea to copious, watery diarrhea with abdominal cramps, fltulence and weight loss- severity is related to immune competence

• usually self limiting
• supportive therapy

• common- source outbreaks
• can be deadly for immunocompromised indeviduals (AIDS)

Prevention: survrilance, portable H2O

Giardia lamblia

• single-celled protists
• flagellate (8)
• ubiquitous( found everywhere worldwide)
• found in GI of infected animals

• Cyst- tough outer shell permits persistence in the environment
• Active Trophozite- colonize upper small intestine

• vehicle- contaminated H2O, reservoirs include beavers, pigs, monkeys
• Direct Contact-infected person fecal-oral

• similar to cryptosporidiosis
• stool contains excessive Lipids(looks greasy, oily)
• Chronic ilness may result in malnourishment

• Metronizadole (cause cancer in rats)
• cause vitamine B-12 malnutrition

• Leishmania tropica or braziliensis
• obligate intracellular parasite

• vector- sandfly
• direct- blood transfusions, vertical

• 2-3 mm
• 30+ species known to transmit leishmania parasites

• 1. Promastigotes- infective flagellate stages, transmit via vector
• 2.Amastigotes- non-flagellate stage( lose flagella), multiplies in animal host tissue

• Cutaneous- one or more skin sores, can lead to partial or total deconstruction of mucous membranes
• Viceral- may take yrs., high fever, progressive weakness and wasting, protrusion of abdomen due to inflimation, fatal if untreated, up to 100% in poverty stricken countries

• Cutaneous-self limiting
• Viceral- Anti-protozoal drugs

• control vector and reservoir (rodant population)
• No vaccine available

• Coinfections wit increase risk of developing viceral disease, accelerate onset of Aids
• Asymptomatic carriers and intravenous drug users contribute to geographic spread of disease

Taxoplasma gondii

• Zoonosis(animal are reservoirs that transmit the disease)
• Primary reservoir- cat

• Vehicle(food, H2O)
• Direct(verticle, fecal-oral)
• *usually is self limiting but treatment is available

• Asymptomatic
• Flu-like illness(healthy non-pregnant pple)
• Congenital Defects

• education hygeine
• avoid exposure

• Trypanosoma brucci
• flagellated
• zoonosis
• 2-23 days incubation

• vector( Tsetse fly, 1 bite=100's of parasites), wils and domestic animals
• vertical

Generalized pain, weakness, shortness of breath,swollen lymphnodes, fever, disturbed vision, anemia, severe headache, tremors, neck pains, uncorrdinated gait, paralysis, deep sleep, malnutrition, emaciation, convulsions, coma,death

• 1. parasite found in peripheral circulation
• 2. parasite crosses BBBinto CNS
• *progression through stages is dependant

• Antitrypanosomes
• antimicribials

• no vaccine
• Vector and reservoir control