Parasitology Lecture 2

Front 1

Apicoplast

Back 1

Derived from chloroplast, 2 phagocytic events, no longer photosynthetic

Front 2

Apicomplexa types

Back 2

1.Plasmodium-1=mosquito, 2=humans
2.babesia-1=tick, 2=mammals
3.toxoplasma gondii-1=cat, 2=mammals
4.cryptosporidium-1=mammals, 2=mammals
5.cyclospora-1=mammals, 2=mammals

Front 3

Apicomplexa Life cycle names (asexual)

Back 3

1.merozoite(ring)
2.trophozoite
3.schizont

Front 4

Apicomplexa Life cycle names (sexual)

Back 4

1.Gametes
2.Oocyst
3.Sporozoite

Front 5

Malaria Epidemiology

Back 5

Developing world-300mill cases, 2mill deaths, 90% in Africa
US-1000 cases

Front 6

Malaria Vector

Back 6

Vector(=1o host) =female mosquitoes(anopheles), bite-night(1am)

Front 7

Malaria Human life stages

Back 7

1.pre-erythrocytic stages(asexual types)
2.erythrocytic asexual stages(asexual types)
3.erythrocytic sexual stages(gametocytes)
4.hypnozoite

Front 8

Malaria clinical course

Back 8

Prepatent period-asymptomatic, multiplying in liver
Paroxysm-shaking chills, then ↑fever(to 106) when RBC burst to release new merozoites, periodic(48-72hrs)

Front 9

Malaria diagnosis

Back 9

1.Giemsa-stained blood smears(thick/thin)
2.Rapid tests
3.Travel history-beware of autochthonous(gotten here)

Front 10

Plasmodium Vivax/ovale

Back 10

1.invade reticulocytes, live in enlarged RBC(schuffner’s dots)
2.produce latent form(hypnozoites)-dormant in liver(months-years then re-initiate parasitemia
3.48hr periodicity

Front 11

Plasmodium Malariae

Back 11

1.NO hypnozoites-persist in blood at low levels
2.72hr periodicity

Front 12

Plasmodium Falciparum

Back 12

1.invade RBC of all ages
2.Sickle-shaped gametocyte(unique)
3.48hr periodicity

Front 13

Why is falciparum malaria the most leathal?

Back 13

Mature P. Facliparum secrete prots into RBC->form Knobs on RBC surface, Knobs cytoadhere to caps and are sequestered->block flow to brain

Front 14

Transmition differences in diseases

Back 14

•High Transmition->adults immune, disease in kids/primigravidae
•Low Transmition->all ages/gravidity

Front 15

Genetics/resistance to malaria

Back 15

1.sickle cell trait
2.thalassemia
3.gluc-6-phosph dehydrogenase deficiency
4.ovalocytosis
5.duffy blood group negative

Front 16

Babesiosis (location, vector, reservoir)

Back 16

1.Intra-erythrocytic parasite(like malaria
2.Tick-borne(ixodes scapularis)
3.Reservoir=white-footed mouse

Front 17

Toxoplasma Gondii Survives How?

Back 17

Survives in Macs-in phagosome by preventing fusion w/ lysosome

Front 18

Toxoplasmosis definitive hosts

Back 18

Only Cats, schizogony+sexual repro in Gut

Front 19

Toxoplasma Gondii Intermediate Hosts

Back 19

1.Humans + 200 other mammals
2.Macs, Fibroblasts, Intestinal epithelium
3.Bradyzoites(cysts)
4.Tachyzoites(trophozoites)

Front 20

Toxoplasmosis Epidemiology

Back 20

Seroprevalence in US=22%
Seroprev. In developing/france is higher (50%)

Front 21

Toxoplasmosis Routes of infection

Back 21

1.Oocyst from cat feces
2.Cyst (bradyzoites) from undercooked meat(steak tartar)

Front 22

Toxoplasmosis Acute disease

Back 22

10-20% develop mono like illness

Front 23

Congenital Toxoplasmosis

Back 23

1.Primary infection during:
•1st trimester->congenital malformations(hydrocephalus, retardation), ocular disease
•2nd/3rd trimester->abortions
2.Non-immune women should avoid cats/raw meat

Front 24

AIDS w/ Toxoplasmosis

Back 24

AIDS Reactivates Latent infection
1.Encephalitis=usually fatal
2.Retinal lesions
3-5% of all opportunistic infections
Protect w/ cotrimoxazole(TMP/SMX) prophylaxis

Front 25

Toxoplasmosis Diagnosis

Back 25

1.Serology
2.Culture/inoculation of mice

Front 26

Toxoplasmosis Treatment

Back 26

1.Antifolates (pyrimethamine/sulfadiazine)
2.Atovaquone

Front 27

Cryptosporidium parvum/hominis/etc. Characteristics

Back 27

1.Cattle pathogen
2.humans in 1976
3.water-bourne in 1985
4.opportunistic w/ AIDS
5.NO Effective Treatment
6.Immunocompetent=mild diarrhea
7.Immunocompromised=severe diarrhea

Front 28

Cryptosporidiosis Transmition paths

Back 28

1.Drinking water
2.swimming pools
3.food

Front 29

Cryptosporidiosis survival characteristic

Back 29

Cysts are chlorine-resistant

Front 30

Cryptosporidiosis Outbreaks

Back 30

>100 in US
Day-care
Municipal water supplies
Big Milwaukee outbreak(400,000 cases)

Front 31

Cryptosporidiosis Epidemiology in immunocompetent

Back 31

•Developing countries-6% of diarrhea
•Developed count.-2% of diarrhea

Front 32

Cryptosporidiosis Epidemiology in HIV

Back 32

•Developing-24% of diarrhea
•Developed-14% of diarrhea

Front 33

Cryptosporidiosis Prevalence

Back 33

Prevalence based on serology in adults
•brazil-100%
•china-60%
•US-20%

Front 34

Cryptosporidiosis Genotypes

Back 34

1.Cryptosporidium Hominis=humans only
2.Cryptosporidium Parvum=Cattle and humans

Front 35

Cryptosporidiosis Genotypes in US/UK

Back 35

C. hominis

Front 36

Cryptosporidiosis genotypes in developing countries

Back 36

Usually C. parvum

Front 37

Cyclospora sp. characteristics

Back 37

1.Looks like Cryptosporidium but bigger
2.same life cycle as Cryptosporidium
3.NO ANIMAL RESERVOIR

Front 38

Cyclosporiasis characteristics

Back 38

1.Looks like cryptosporidium but bigger
2.Causes illness like cryptosporidium
3.2-20% prevalence in developing count.

Front 39

Cyclosporiasis outbreaks

Back 39

In N. America due to imported Guatemalan raspberries

Front 40

Cyclosporiasis treatment

Back 40

bactrim