Malaria/Babesia

Question 1

malaria parasite

Answer 1

phylum: apicomplexa
genus: plasmodium
protozoa
single celled eukaryotic parasite

Question 2

4 species infecting humans

Answer 2

plasmodium. ..
- falciparum
- vivax
- ovale
- malariae

Question 3

plasmodium knowlesi

Answer 3

monkey malaria
emerging infections
malayaia, SE asia

Question 4

malaria deaths

Answer 4

627,000
90% in africa
mostly < 5 yo
20% of child mortality in africa

Question 5

clinical cases of malaria

Answer 5

150-300 million/yr

> 90% is tropical africa

Question 6

^malaria risk

Answer 6

pregnancy

children

Question 7

main cause of severe malaria

& malaria death

Answer 7

plasmodium falciparum

Question 8

malaria transmission

Answer 8

mosquito (anopheles)

rare: mother to child, blood transfusion

Question 9

malria vector

anopheles mosquito

Answer 9

female only
definitive host (sexual stage)

Question 10

cause of uncomplicated

malaria

Answer 10

all species of plasmodium

Question 11

complicated/severe malaria

Answer 11

plasmodium falciparum

Question 12

uncomplicated malaria sxs

Answer 12

fever, chills, sweats
NVD
headache
sxs coincides w rupture of RBCs

Question 13

tertian malaria

Answer 13

fever every 2 days

P. vivax/ovale

Question 14

quartan malaria

Answer 14

fever every 3 days

P. malariae

Question 15

irregular fever

Answer 15

P. falciparum

Question 16

malaria sxs prevalence

Answer 16

fever 96%
fever > 39C 30%
splenomegaly 26%
elevated LDH 78%
thrombocytopenia 58%

Question 17

complicated malaria

P. falciparum

Answer 17

cerebral malaria (seizure, coma, posturing)
severe anemia
hypoglycemia
resp distress, pulm edema
hyperparasitemia
renal failure ("blackwater fever")
acidemia/acidosis
circulatory failure/shock

Question 18

complicated malaria

P. vivax

Answer 18

severe disease in 4%
splenic rupture
possibly fatal

Question 19

complicated malaria

P. knowlesi

Answer 19

< 10% of cases

respiratory distress

Question 20

malarial pulmonary edema

Answer 20

P. falciparum
non cardiogenic
more common in adults
cause unclear (possibly cytokine release)
poor prognotic sign

Question 21

acquired resistance

Answer 21

incomplete (infection w/o sxs)
occurs slowly w age
depends on level of exposure
can be lost w/o continued exposure

Question 22

duffy antigen

Answer 22

RBC antigen required for P. vivax
invasion
absent in west africans

Question 23

sickle cell trait

Answer 23

protective against P. falciparum

Question 24

pregnancy risk

Answer 24

resistance lost during 1st pregnancy
and regained in subsequent pregnancies
(except if HIV+)

Question 25

malaria in pregnancy

Answer 25

higher mortality
anemia (mom&baby)
low birth weight
infant mortality
drug therapy 2/more times during 
pregnancy recommended

Question 26

Imported Malaria (US)

Answer 26

1500 per year acquire malaria visting
family internationally
50% P. falciparum

Question 27

malaria dx

Answer 27

microscopy (blood smear)
PCR
serology not useful in acute infection

Question 28

light microscopy

Answer 28

thick or thin film
finger stick (capillary blood best)
identifies ssp and infection level

Question 29

BinaxNOW

Answer 29

rapid dx test (blood drop)
detects all 4 ssp
only validated for Pf & Pv

Question 30

liver hypnozoites

Answer 30

normal infection w P. ovale/vivax

not killed by chloroquine

Question 31

choroquine

Answer 31

^ resistance: P. falciparum

rare resistance: P. vivax, ovale, malariae

Question 32

malaria drugs

Answer 32

artemesinin-based combo therapies (ACT)
mefloquine
atovaquone-pyrimethamine
amodiaquine

Question 33

severe malaria tx

Answer 33

IV/IM quinine or artemesinin
rectal artesunate in children < 5
fluids, +/- blood transfusion

Question 34

P. ovale/vivax tx

Answer 34

tx hypnozoite stage
primaquine x 14 days
screen for G6PD first (drug will cause hemolytic crisis)

Question 35

artemesinins

Answer 35

derived from qinghoa plant

degrade heme to produce C free radicals

Question 36

fixed dose combos (ACT)

Answer 36

Artemether-lumefantrine (Coartem®)
Dihydroartemisinin-piperaquine (Artekin®)
Artesunate & chlorproguanil-dapsone(Lapdap®)

Question 37

parenteral artesunate

Answer 37

available from CDC

Question 38

IV quinidine

Answer 38

requires cardiac and glucose

monitoring

Question 39

malaria prevention for travelers

Answer 39

insect repellent
insectiside treated bednets
chemoprophylaxis before, during, after

Question 40

barriers to malaria

elimination

Answer 40

drug resistance
socio-political change
environmental change
HIV/AIDS
insecticide resistance

Question 41

malaria vaccine

asexual blood stage

Answer 41

protects mosquitos not humans
prevents furthur spread from infected
individual

Question 42

babesia

Answer 42

apicomplexan parasite
intraerythrocytic protozoa
4 human infective ssp
most US illness B. microti

Question 43

babesia vector

Answer 43

tick-bourne (ixodes scapularis)
same tick as lyme
requires >24hrs attachment

Question 44

babesia reservoir

Answer 44

white footed mouse

Question 45

babesia endemic

Answer 45

coastal southern new england, wisconsin,
minnesota
occurs in summer
can by transmitted via blood transfusion

Question 46

assymptomatic babesiosis

Answer 46

> 25% of cases

>50% in children

Question 47

babesiosis clinical

presentation

Answer 47

incuvation 1-6 wks
flu-like sxs (wks-months): fever, chills, 
fatigue, headache
complications: ARDS, massive hemolysis, 
CHF, renal failure, death

Question 48

Babesiosis High Risk

Answer 48

elderly

asplenic (parasitemia uncontrolled)

Question 49

babesiosis dx

Answer 49

microscopy of blood:
giemsa stain, tetrads, maltese cross
serology (IFA)
PCR
xenodiagnosis in hamster (not rountine)

Question 50

baesiosis tx

Answer 50

mostly self limiting
severe/symptomatic tx:
- atovaquone+azithromycin
- clindamycin+quinine

Question 51

babesiosis + HIV

Answer 51

long term supressive tx req

Question 52

borrelia burgdorferi

co infection

Answer 52

must be ruled out when babesiosis

is present