Virology Quiz 2 Paramyxoviruses And Slow Viruses

Front 1

is influenza normally a systemic infection? Does it normally cause viremia?

Back 1

no; no

Front 2

is parainfluenza normally a systemic infection? Does it normally cause viremia?

Back 2

no; no

Front 3

what is the family of measles and mumps? Are they systemic? Do they cause viremia?

Back 3

paramyxoviruses; yes; yes

Front 4

is the incubation period of systemic or nonsystemic infections longer? Why?

Back 4

systemic; because cycles of multiplication in multiple sites are required

Front 5

for systemic infections, how long does immunity last? Which kind of Ab is produced?

Back 5

for life; IgG

Front 6

what kind of nucleocapsid symmetry do measles and mumps have? What type of genome do they have?

Back 6

helical; - ssRNA

Front 7

which, measles, or mumps, is antigenically related to parainfluenza? Which is not?

Back 7

mumps; measles

Front 8

do measles and mumps agglutinate red blood cells?

Back 8

yes

Front 9

how common is recombination of measles and mumps RNA?

Back 9

very rare, because the RNA is only one piece

Front 10

what is the usual presenting symptom of mumps?

Back 10

parotiditis

Front 11

what is the time frame during which mumps virus is secreted into the saliva?

Back 11

several days before and after swelling of the salivary gland begins

Front 12

how is mumps spread once it is inhaled by someone?

Back 12

saliva droplets infect the upper respiratory tract then primary multiplication in the respiratory epithelium and local lymph nodes

Front 13

do the virions of the mumps virus travel up the parotid duct to the gland?

Back 13

no, they reach the parotid gland via viremia

Front 14

in what percentage of males is orchitis seen in mumps infections? How often does this result in sterility?

Back 14

10%; rarely

Front 15

other than the parotid gland and testis, what other organs are affected by the mumps virus?

Back 15

pancreas, ovary, meninges.

Front 16

if the mumps infection is subclinical or only affects one parotid, how long does immunity last?

Back 16

for life

Front 17

what type of vaccine is given for mumps?

Back 17

live-attenuated

Front 18

why is worldwide eradication of mumps not a high priority?

Back 18

due to low morbidity and low mortality

Front 19

is measles very contagious?

Back 19

yes, one of the most contagious diseases

Front 20

how common are subclinical infections for measles?

Back 20

extremely rare

Front 21

before the measles vaccine, what was the method behind the cyclic epidemics that occurred every 3 years?

Back 21

due to new births, number of susceptibles increased over 3 years. When the concentration of susceptibles was sufficient to break down herd immunity, epidemic occurred

Front 22

how does the measles virus infect? Where does it multiply?

Back 22

via the respiratory tract; in epithelium and local lymph nodes

Front 23

which occurs first, viremia or rash, in measles? By how many days?

Back 23

viremia precedes rash by 3 days

Front 24

with which predromal symptoms is the measles virus associated?

Back 24

fever, cold-like symptoms, Koplik spots, conjunctivitis, and photophobia

Front 25

how long is the incubation period for measles?

Back 25

14 days

Front 26

does the immune system play a role in the measles rash?

Back 26

it may -- unknown

Front 27

when is measles virus excreted in tears and urine and via resp system?

Back 27

for a few days before and after the appearance of the rash

Front 28

how long does the immunnity confered for measles virus last ?

Back 28

life long

Front 29

what is the pathology hallmark of a measles virus infection?

Back 29

formation of multi-nucleate giant cells by fusion

Front 30

what are the steps in cellular fusion in a measles virus infection?

Back 30

1) infection of four-celled tissue 2) viral Ag in membrane of first infected cell 3) cell fusion spreads the infection to adjacent cells

Front 31

what is the effect of the measles virus on cell-mediated immunity? What is the name for this?

Back 31

it is suppressed; anergy

Front 32

what do many measles victims die of secondary infections?

Back 32

because the cell-mediated immunity is suppressed

Front 33

why does the measles virus need a large, concentrated population to survive?

Back 33

because the virion is unstable, it must be growing in some individual somewhere at all times

Front 34

what are the 4 complications of measles in the developed countries?

Back 34

encephalitis, pneumonia, otitis media, and giant-cell pneumonia

Front 35

is there a rash present in the giant-cell pneumonia often associated with the measles virus? Why or why not?

Back 35

because there is no cell-mediated immunity

Front 36

does lifelong measles immunity require restimulation by contact with exogenous virus? Do immune invididuals excrete infectious virus?

Back 36

no; no

Front 37

what is the effect of agammagobulinemia on viral infections?

Back 37

nothing -- these people normally recover normally from viral infections and have long-term immunity to reinfection.

Front 38

what is the mortality rate of measles virus in developing countries?

Back 38

5-25%

Front 39

with which virus is a severe hemorrhagic rash associated in developing countries?

Back 39

measles virus

Front 40

what effect does treatment of measles victims in developing countries with vitamin A have on the infection? Why?

Back 40

substantially reduces the mortality; because it helps to reduce the malnutrition

Front 41

what type of vaccine is given for measles?

Back 41

live-attenuated

Front 42

what characterizes the infection of subacute sclerosing panencephalitis? Is it normally fatal or not?

Back 42

insidious onset of intellectual deterioration, psychological disturbances with slow decline interrupted by remissions; yes, with terminal blindness and paralysis

Front 43

at what age is SSPE most commonly seen? How was it originally identified as a distinct disease?

Back 43

school-age; inclusion bodies

Front 44

what characterizes the Ab titers of SSPE patients?

Back 44

very high Ab titers to measles virus

Front 45

what viral antigen is present in abundance in SSPE patients?

Back 45

measles virus

Front 46

what is the relationship between measles viral infection and development of SSPE?

Back 46

all patients were infected many years (4-17) earlier by measles virus (usually before age 2)

Front 47

how does measles virus cause SSPE?

Back 47

unknown

Front 48

has SSPE been detected in people who have received the measles vaccine but who have never had the disease?

Back 48

yes, but very rare

Front 49

are slow viral infections normally localized or systemic?

Back 49

generally isolated to one organ

Front 50

what is scrapie?

Back 50

a chronic progressive CNS disorder of adult sheep

Front 51

what infectious process is associated with scrapie?

Back 51

none known

Front 52

which sheep are most susceptible to scrapie?

Back 52

inbred lines

Front 53

how long is the incubation period of scrapie in mice?

Back 53

less than a year

Front 54

how does the scrapie agent respond to UV irradiation, formaldehyde, and alkylating agents?

Back 54

resistant

Front 55

what is the name given to the scrapie agent?

Back 55

prion

Front 56

which part of the sheep brain is normally affected by scrapie?

Back 56

cerebellum

Front 57

what is kuru?

Back 57

a progressive degenerative disorder of the CNS, especially the cerebellum

Front 58

what population is afflicted with kuru?

Back 58

small stone-age tribe in New Guinea

Front 59

at its peak, what percentage of the tribe did kuru kill off?

Back 59

50

Front 60

what is the neuropathology of kuru?

Back 60

spongiform encephalopathy

Front 61

can kuru be transmitted by ingestion of infected brains?

Back 61

yes

Front 62

why is the incidence of kuru down?

Back 62

becayse of reduced cannibalism

Front 63

what is the name of the most common form of spongiform encephalopathy?

Back 63

creutzfeld-jacob

Front 64

is creutzfeld-jacob disease normally an inherited disease or spontaneous?

Back 64

mostly spontaneous

Front 65

how did mad cow disease spread in england?

Back 65

by including cow and sheep bone marrow and brains in cow feed.