Final; Childhood Viral Diseases

Question 1

What is the genome of the measles virus

Answer 1

-ssRNA

Question 2

What type of virion does the measles virus have

Answer 2

enveloped

Question 3

The fusion protein in the measles virus causes what

Answer 3

syncytia (mass containing several nuclei) formation

Question 4

How is the measles virus transmitted

Answer 4

inhalation of aerosolized droplets

Question 5

What is the incubation period of the measles virus

Answer 5

10-14 days

primary infection in respiratory epithelial tissues; primary viremia

Question 6

What is characteristic of the the symptom onset of measles

Answer 6

the symptoms onset coincides with the second round of virus replication
occurs in LN, tonsils, lungs, GI tract, and spleen; secondary viremia

Question 7

What is the recovery time for measles

Answer 7

approximately 20 days after infection

Question 8

True or False

Measles is the most deadly of childhood rash/fever illnesses

Answer 8

True

Question 9

What causes the characteristic rash of measles

Answer 9

viral and immune response damage to epithelial and endothelial cells
koplik spots

Question 10

How does measles influence immune suppression

Answer 10

Interferes with CD46 and signaling lymphocyte activation molecule (SLAM) receptors
also allows opportunistic infections

Question 11

This is a rare; 1:1000 in children demyelinating disease

Answer 11

acute disseminated encephalitis (ADEM)

Question 12

This is very rare; 1:1million in children, 7-10 years after infection, progressive neurological deterioration

Answer 12

subacute sclerosing panencephalitis (SSPE)

Question 13

What are the symptoms of measles

Answer 13

2-3 days fever and cough, coryza, and conjunctivitis

characteristic rash

Question 14

How is measles diagnosed in the laboratory

Answer 14

virus isolation in culture (difficult)
serology
ELISA, RT-PCR

Question 15

True or False

Measles is not very contagious

Answer 15

False; it is one of the most contagious diseases known

Question 16

How much can humans spread measles

Answer 16

they are the only host
one illness in a naïve population can infect 15-20 people
people are infectious 2-3 prior to rash

Question 17

What are some ways in preventing measles

Answer 17

vaccination (provides life long immunity)
vitamin A
there are no anti-virals

Question 18

When was measles considered “eliminated” from the US

Answer 18

2000, but it is common in other countries

it arrives to the US through international travel

Question 19

What is the genome of the respiratory syncytial virus

Answer 19

-ssRNA

Question 20

What type of virion does the respiratory syncytial virus have

Answer 20

enveloped

Question 21

What type of cells does the respiratory syncytial virus infect

Answer 21

ciliated ells in the respiratory tract epithelium

Question 22

This protein in the respiratory syncytial virus creates the syncytia

Answer 22

fusion protein

Question 23

How does the virus exit the cell

Answer 23

via budding

Question 24

What is special about the respiratory syncytial virus in regards to respiratory tract infections

Answer 24

it is the most important viral agent of serious pediatric respiratory tract infections

Question 25

How does one obtain the respiratory syncytial virus

Answer 25

via inhalation of aerosol | fomites

Question 26

What is the incubation period of respiratory syncytial virus and where is it specifically found

Answer 26

4-5 days | lower respiratory tract 1-3 days after upper respiratory tract

Question 27

How long is the recovery of the respiratory syncytial virus

Answer 27

7-12 days after symptom onset

Question 28

Does the respiratory syncytial virus infect animals?

Answer 28

No, it only infects humans, no animal reservoir

Question 29

Does respiratory syncytial virus infection result in life long immunity?

Answer 29

No, infants have an immature immune system and in the respiratory tract IgA is short lived

Question 30

What are some risk factors for respiratory syncytial virus infection

Answer 30

attending day care | school aged siblings

Question 31

What would put someone at risk for a more severe respiratory syncytial virus infection

Answer 31

premature birth male second-hand exposure to tobacco smoke lack of breast feeding

Question 32

What is the main prevention of the respiratory syncytial virus

Answer 32

no antivirals no vaccine can use passive immunoprophylasis; humanized monoclonal antibody (once a month)

Question 33

What is the genome of the varicella zoster virus

Answer 33

dsDNA

Question 34

What is the virion of the varicella zoster virus

Answer 34

enveloped

Question 35

What is the main difference about the proteins varicella zoster virus produces

Answer 35

there are hundreds of proteins

Question 36

What is the replication of the varicella zoster virus

Answer 36

active cell needed for replication resting cell (neuron) = latent infection (circular genome) will infect neighboring cell first

Question 37

What is the transmission of the varicella zoster virus

Answer 37

inhalation of aerosolized droplets

Question 38

What is the incubation period for the varicella zoster virus

Answer 38

10-21 days

Question 39

What are the symptoms of the varicella zoster virus

Answer 39

chicken pox; fever, malaise, headache rash 1-2 days after the symptom onset, lasting for 3-6 days

Question 40

Where is the chickenpox rash primarily located

Answer 40

scalp, face, and trunk

Question 41

What is the recovery timeframe of the varicella zoster virus

Answer 41

usually by 2 weeks of symptom onset; cell mediated immunity most important

Question 42

What happens upon re-activation of the varicella zoster virus

Answer 42

shingles

Question 43

What are the prevention strategies of chickenpox

Answer 43

vaccination; life long immunity | antivirals; but it cannot eliminate latent virus because the DNA is not actively being replicated

Question 44

What is the genome of the poliovirus

Answer 44

+ssRNA

Question 45

What is the virion of the poliovirus

Answer 45

non-enveloped

Question 46

What specific proteins does the poliovirus contain

Answer 46

4 protein capsid

Question 47

What does the virus particle do to the cell

Answer 47

it creates a pore in the cell membrane

Question 48

Where is the poliovirus prevalent

Answer 48

in endemic areas such that infections are most common in naïve children

Question 49

How is the poliovirus transmitted

Answer 49

ingestion of material infected by the virus

Question 50

Where is the location of the poliovirus manifestation

Answer 50

Peyers patches of the small intestine; minor viremia secondary replication; major viremia mild disease

Question 51

How long does fecal shedding of the poliovirus occur

Answer 51

for 2 weeks

Question 52

How prevalent is CNS involvement in polio

Answer 52

1:200 of infections | risk factors; physical exertion, trauma, and tonsillectomy

Question 53

How does the poliovirus affect the CNS

Answer 53

it replicates in the gray matter of brain and spinal cord limb paralysis from anterior horn damage respiratory paralysis from damage to the medulla oblongata

Question 54

What are the prevention strategies of the poliovirus

Answer 54

vaccination; 2 available | targeted for eradication

Question 55

What is the genome of the rotavirus

Answer 55

dsRNA, 11 segments

Question 56

What is the virion of the rotavirus

Answer 56

non-enveloped

Question 57

What is special about the rotavirus replication

Answer 57

there is membrane disruption | genome is never exposed

Question 58

How is rotavirus transmitted

Answer 58

ingestion of material containing the virus

Question 59

What is the incubation of rotavirus

Answer 59

2 days; vomiting and fever

Question 60

What are the symptoms of rotavirus

Answer 60

diarrhea 2-3 days after vomiting, 3-8 days in duration

Question 61

How long does viral shedding last

Answer 61

weeks before symptom onset and days after the recovery

Question 62

When is severe disease of rotavirus common

Answer 62

most common is 6-24 month children

Question 63

How is rotavirus diagnosed

Answer 63

antigens in the stool

Question 64

What are the prevention strategies of rotavirus

Answer 64

infant vaccines no antivirals good hygiene treatment via oral rehydration