MICRO

Question 1

what are the 4 reasons that smallpox was able to be eradicated?

Answer 1

1. humans are the only reservoir
2. no healthy carriers
3. no sub-clinical infections
4. effective vaccine available

Question 2

what causes molluscum contagiosum?

Answer 2

pox virus

Question 3

what is molluscum contagiosum?

Answer 3

Childhood form
--lesions on the face, trunk and limbs
--spread from skin to skin
--mostly tropical
Young adult form (mostly lower abd. lesions, sexually transmitted)

Question 4

how do you diagnose molluscum contagiosum?

Answer 4

by appearance, confirmed by presence of cytoplasmic inclusions in eosinophils of the affected area

Question 5

when does a person with smallpox stop being contagious?

Answer 5

when the last scab has fallen off

Question 6

when does a pt with parvoB19 stop being contagious?

Answer 6

once the rash appears

Question 7

where does smallpox virus replicate?

Answer 7

in the cytoplasm of infected cells

Question 8

E. chaffeensis (HME) replicates in which kind of cells?

Answer 8

monocytes

Question 9

A. phagocytophilia (HGA) replicates in which kind of cells?

Answer 9

granulocytes

Question 10

which bug causes cat scratch disease?

Answer 10

bortonella henselae

Question 11

which bug causes lyme disase?

Answer 11

borrelia burgdorferi

Question 12

what is the classic skin finding with lyme disease?

Answer 12

bullseye lesion

Question 13

what is the classic skin finding in cat scratch disease?

Answer 13

swollen gland near site of scratch

Question 14

which bug causes epidemic typhus?

Answer 14

R. prowazekii

Question 15

which bug causes rocky mountain spotted fever?

Answer 15

R. rickettsia

Question 16

describe the rash in Rocky mountain spotted fever

Answer 16

spreads from ankles and wrists to soles, palms, trunk

Question 17

most measles mortality is due to what?

Answer 17

secondary bacterial infections and pneumonia

Question 18

what disease was the leading cause of aseptic meningitis prior to development of vaccine?

Answer 18

mumps

Question 19

orchitis in post-pubertal men is the major complication of what diseaes?

Answer 19

mumps

Question 20

which virus causes a mild disease but is a serious threat to the fetus?

Answer 20

rubella

Question 21

why was the MMR vaccine so successful?

Answer 21

all 3 viruses are monotypic (only 1 serotype)

humans are the only known reservoir

Question 22

which highly contagious pathogen causes significant immune suppression and has associated neurological complications?

Answer 22

measles

Question 23

This pathogen has the H protein rather than the HN and also forms inclusion bodies:

Answer 23

measles virus

Question 24

what are the contraindications to the MMR and the varicella vaccine?

Answer 24

severe allergic rxn
pregnancy
immunodeficiencey

Question 25

what is the downside to taking the MMRV instead of MMR and varicella vaccines separately?

Answer 25

taking the MMRV has an increased risk of fever and febrile seizures

Question 26

which virus causes the roseola rash?

Answer 26

HHV6 & HHV7

Question 27

what types of pts get the roseola rash?

Answer 27

children 3months - 6 yrs

Question 28

what kind of genome does the herpes viruses have?

Answer 28

linar, ds DNA genome, icosahedral capsid, enveloped

Question 29

is VZV neurotropic or lymphotropic?

Answer 29

neurotropic

Question 30

is HHV6 & HHV7 neurotropic or lymphotropic?

Answer 30

lymphotropic

Question 31

where do you usually see leprosy affecting the pt (antomically)?

Answer 31

face, butt, limbs

Question 32

you might get lepromatous leprosy if you lack what type of immune response?

Answer 32

Th1 mediators

Question 33

how do you diagnose leprosy?

Answer 33

clinical w/ confirmation from skin biopsies and detection of AFB (can't be grown in culture)

Question 34

other than humans, who gets leprosy?

Answer 34

armadillos

Question 35

how do you treat tuberculoid leprosy?

Answer 35

dapsone & rifampin for 6 months

Question 36

how do you treat lepromatous leprosy?

Answer 36

dapsone & rifampin + clofazime (for 2 yrs)

Question 37

what type of genome does the parvovirus B19 have?

Answer 37

ss DNA icosahedral no envelope

Question 38

what causes erythema infectiosum?

Answer 38

ParvoB19

Question 39

which pathogen causes the slapped cheek rash and lacy rash (on trunk and limbs)?

Answer 39

ParvoB19

Question 40

what kind of genome does smallpox have?

Answer 40

large dsDNA that is enveloped

Question 41

what would be the cause of death in a pt who had smallpox?

Answer 41

due to toxic effects on vascular endothelium

Question 42

when is a patient with smallpox the most contagious?

Answer 42

when the small red spots in the mouth and tongue rupture

Question 43

how do you distinguish between smallpox and chickenpox?

Answer 43

smallpox has febrile prodrome (chickenpox doesnt) smallpox are firm and well defined, (chickenpox are superficial) smallpox lesions will all be at the same stage (chickenpox won't)

Question 44

where is relapsing fever endemic?

Answer 44

high, dry areas of western US

Question 45

what accounts for the relapsing fever in borrelia?

Answer 45

antigenic variation

Question 46

how might a pt acquired leptospirosis?

Answer 46

contact w/ water contaminated with animal urine, usually through a break in the skin

Question 47

why are the symptoms assoicated w/ leptospirosis?

Answer 47

DOESN'T CAUSE SKIN LESIONS Flu-like symptoms Jaundice & renal damage (Weil's disease) Meningitis

Question 48

how do you diagnose leptospirosis?

Answer 48

serology

Question 49

how do you treat leptospirosis?

Answer 49

penicillin

Question 50

how do you diagnose E. chafeensis?

Answer 50

blood smear | confirm w/ serology

Question 51

how do you diagnose A. phagocytophilia?

Answer 51

blood smear (look for morulae in granulocytes)

Question 52

how do you treat the Rickettsial diseases?

Answer 52

DOXY

Question 53

how do you diagnose relapsing fever?

Answer 53

blood smear w/ serology to confirm

Question 54

Measles virus uses which 2 notable receptors?

Answer 54

CD46 & SLAM

Question 55

what is the measles clinical case definition?

Answer 55

gen. rash lasting>3 days Temp. > 38.3 Cough, rhinorhea, and/or conjunctivitis (light sensitivity)

Question 56

where does the MV replicate?

Answer 56

most lymphatic tissues and organs throughout the body (epithelial, endothelial, mphages, monocytes)

Question 57

describe the classic measles rash?

Answer 57

starts on the back of the neck or forehead and spreads to extremities

Question 58

The neurological measles virus complications are the result of an autoimmune response to what protein?

Answer 58

myelin basic protein

Question 59

what is acute disseminated encephalomyelitis or postinfectious encephalomyelitis?

Answer 59

neurological Measles complication resulting in convulsions, deafness, mental retardations

Question 60

describe the classic rubella rash?

Answer 60

morbilliform and starts on the face and spreads to the rest of the body

Question 61

how is measles different than the other paramyxoviridae?

Answer 61

Has H protein instead of HN | forms intracellular inclusion bodies