E2- Viral Skin Infections

Question 1

In which populations can Measles be severe in?

Answer 1

Can be severe in malnourished and/or vitamin A deficient persons

Question 2

What is the causative agent of measles?

Answer 2

Rubeola

Question 3

What are the four stages of Measles infection?

Answer 3

1. Incubation
2. Prodromal
3. Rash
4. Resolution

Question 4

Where does Measles replicate?

Measles disseminates to other tissues by what?

Answer 4

Respiratory epithelium and lymph nodes

Monocytes

Question 5

Multiplication of virus in respiratory epithelium and lymph nodes and dissemination to other tissues by monocytes is seen in which stage of Measles?

Answer 5

Incubation period

Question 6

What is the characteristic presentation in the prodromal stage of Measles?

Answer 6

High fever
Coryza, persistent cough, conjunctivitis (the 3 Cs)
Koplik’s spots on buccal mucosa (diagnostic)

Question 7

What is diagnostic for Measles?

Answer 7

Koplik’s spots on buccal mucosa

Question 8

When does a Measles rash appear?

Answer 8

3-4 days after prodrome initiates

Question 9

What is seen in the rash stage of Measles?

Answer 9

Highest fever (sickest patient)
Begins below ears, spreads

Question 10

What is seen in the resolution stage of Measles?

Answer 10

Rise in antibody titers, viremia stops

Rash fades in same order that it appears

Question 11

What are complications of Measles?

Answer 11

Pneumonia
Diarrhea
CNS involvement (Encephalitis)

Question 12

What is the most common cause of Measles death?

Answer 12

Pneumonia (bacterial superinfection common)

Question 13

What CNS effects can Measles cause?

Answer 13

Acute symptomatic encephalitis
High fatality rate
SSPE - subacute sclerosing panencephalitis (very rare in U.S.)

Question 14

Besides humans, what is the only other species that can act as a Measles host?

Answer 14

Monkeys

Question 15

Is there a healthy carrier state of Measles?

Answer 15

NO

Question 16

What age group is most commonly affected by Measles?

Answer 16

Disease of children (most immune by age 10)

Rare in infants under 6 mo (maternal immunity)

Question 17

How is Measles transmitted?

Answer 17

Respiratory droplets (highly contagious)

Question 18

How is Measles dx?

Answer 18

Rash and/or Koplik’s spots
Serology
Fluorescent antibody test on cells obtained from swabs of pharynx, nasal and buccal cavities
(multi-nucleated giant cells)

Question 19

How is Measles controlled?

Answer 19

MMR vaccine

Question 20

What can you use for patients exposed to measles who are non-immune subjects?

Answer 20

Immune globin (BayGam)
- must be used within 6 days of exposure

Question 21

When is the MMR vaccine given?

Answer 21

15 months -first dose
4-6 -second dose
+/- 3rd dose
May vaccinate children under 15 mo with monovalent measles vaccine if exposure is likely

Question 22

What type of MMR vaccine is used in the US?

Answer 22

MMR II

Live, attenuated vaccine, not suitable for all patients

Question 23

What percent of the population must be vaccinated to halt Measles persistence in the population?

Answer 23

95%

Question 24

What is the most common cause of Measles outbreaks in the US?

Answer 24

Non-vaccinated person and air travel to foreign locations

Question 25

What is the causative agent of German Measles?

Answer 25

Rubella

Question 26

What is probably needed for Rubella infection?

Answer 26

Close and prolonged contact | many children often escaped infection

Question 27

Maternal infection (viremia) during _____ may lead to placental infection and fetal infection.

Answer 27

First trimester of pregnancy

Question 28

What is a complication of Rubella?

Answer 28

Congenital Rubella Syndrome (CRS)

Question 29

How does Congenital Rubella Syndrome (CRS) present?

Answer 29

Cardiac defects Eye defects (cataracts, glaucoma) Hearing loss CNS involvement

Question 30

Who should never receive the MMR vaccine?

Answer 30

Pregnant women (especially in first trimester; live vaccine)

Question 31

If non-immune mother is exposed to Rubella, what may you give prophylatically?

Answer 31

Immunoglobin (IVIG)

Question 32

What two properties influence the disease capacity of HSV?

Answer 32

Capacity to invade and replicate in CNS | Ability to establish latent infections

Question 33

HSV will cause a _____ that will resolve and establish a ____ state of latency subject to reactivation

Answer 33

HSA will cause a primary infection (may be asymptomatic) that will resolve and establish a quasi-stable state of latency subject to reactivation (recrudenscence)

Question 34

How does HSV present?

Answer 34

Shallow vesicles on an erythematous base | Ballooning pathology, vesicles crust over (painful)

Question 35

How does the HSV virus remain latent?

Answer 35

Retrograde transport of virus through sensory neurons and ultimate infection of the dorsal root ganglia

Question 36

How long does HSV latency last?

Answer 36

Life-long

Question 37

What are some things that can reactivate HSV?

Answer 37

Sunlight, stress, menses, nutrition

Question 38

What halts continued spread of HSV?

Answer 38

Cell and humoral immune process

Question 39

____ will occur even in the presence of active humoral and cellular immunity?

Answer 39

Recrudescence

Question 40

The probability of recrudescence is greater in individuals with what?

Answer 40

Larger and more extensive initial outbreaks

Question 41

What species can act as a reservoir for HSV?

Answer 41

Humans

Question 42

How is HSV spread?

Answer 42

Contact with vesicular fluid, saliva, and secretions

Question 43

Is asymptomatic HSV shedding possible?

Answer 43

YES

Question 44

What type of HSV infection is most common and when does it usually occur?

Answer 44

HSV-1 | Early in life

Question 45

What type of HSV infection usually occurs later in life and is associated with sexual activity?

Answer 45

HSV-2

Question 46

HSV disseminates in the absence of ____.

Answer 46

Immune response

Question 47

How is HSV dx?

Answer 47

``` Direct samples of tissue Ballooning pathology Presence of enlarged and fused cells FA assay for vital antigens Culture PCR Antibody tests ```

Question 48

What is the causative agent of chickenpox and shingles?

Answer 48

Varicella-zoster virus (VZV) | herpes zoster

Question 49

How does chickenpox present?

Answer 49

Asymmetrical vesicular rash Follows dermatomal pattern Fever, malaise, headache, neuralgia Lesions pruritic

Question 50

How does chickenpox virus spread?

Answer 50

Conjunctiva or respiratory tract mucosa | virus also present in vesicles

Question 51

Where does chickenpox replicate? When?

Answer 51

Lymph nodes primary viremia 4-6 days after infection | Liver and spleen secondary viremia (coincident with rash) 10-14 days after infection

Question 52

Who are the only species can act as a reservoir for VZV?

Answer 52

Humans

Question 53

When is a pt that is infected with VZV most contagious?

Answer 53

1-2 days before appearance of lesions and 4-5 days after

Question 54

How is chickenpox dx?

Answer 54

Clinical findings | Rash and fever

Question 55

VZV may be tricky to distinguish from HSV in what patients?

Answer 55

Immunocompromised and neonates

Question 56

Is aspirin recommended for tx of chickenpox? Why?

Answer 56

No, Reyes syndrome risk

Question 57

What vaccine can be used to prevent chickenpox?

Answer 57

Varivax (live vaccine)

Question 58

Can you still get chickenpox if you have been vaccinated?

Answer 58

Yes

Question 59

_____ during pregnancy can produce significant disease.

Answer 59

Congenital/neonatal VZV

Question 60

Why might some parents have a Rubella "Party?"

Answer 60

They believe that obtaining the actually infection is superior to the vaccine because they will obtain life-long immunity (FALSE)

Question 61

What can VZV can remerge as ____

Answer 61

Shingles

Question 62

How does Shingles present?

Answer 62

Painful lesions in unilateral dermatomal distribution (searing, burning, stabbing) Pain may precede rash by days to weeks Area of redness evolves to papules to vesicles in 24 hour period Low grade fevers, anorexia

Question 63

What nerves may Shingles involve?

Answer 63

Ophthalmic branch of the 5th cranial nerve (ocular involvement)

Question 64

What is the most common complication of Shingles?

Answer 64

Postherpetic neuralgia

Question 65

What is an absolute prerequisite for Shingles?

Answer 65

Chickenpox or Varivax vaccination (not directly transmissible)

Question 66

How is Shingles prevented?

Answer 66

Zostavax vaccine | Shingrix vaccine

Question 67

Who is Zostavax indicated for?

Answer 67

Pts over 50 | Same virus used in Varivax, but higher potency

Question 68

Who is Shingrix indicated for?

Answer 68

Prior Zostavax recipients, may replace Zostavax

Question 69

What is Roseola Infantum (6th Disease) caused by?

Answer 69

Human Herpes Virus-6 | HHV-6

Question 70

What is one of the most regularly acquired viral infections of childhood?

Answer 70

HHV-6

Question 71

How does HHV-6 present?

Answer 71

Sequence of fever followed by a sudden rose-colored rash

Question 72

How is HHV-6 dx?

Answer 72

Detection of antibody by EIA | DNA sequence detection by PCR amplification

Question 73

What causes Erythema infectiosum (fifth disease)?

Answer 73

Parvovirus B19

Question 74

How does Parvovirus present?

Answer 74

Prodromal illness of several days duration with mild symptoms Followed by maculopapular rash (slapped cheek appearance, circumoral sparing) Arthralgia, arthritis (in adults)

Question 75

What age population has the highest incidence of Parvovirus?

Answer 75

School age children (elementary schools)

Question 76

How is Parvovirus dx?

Answer 76

Facial rash helpful Detection of anti B19 IgM antibody Epidemic outbreaks aid diagnosis

Question 77

HPV 6 and 11 produce what?

Answer 77

Anogenital warts

Question 78

HPV 16 and 18 produce what?

Answer 78

Cervical dysplasia and cancer

Question 79

How is HPV prevented?

Answer 79

Vaccines are available to prevent HPV sexually transmitted infection Gardasil 9- HPV 6, 11, 16, 15, and 5 others

Question 80

What age groups can you give the Gardasil vaccine to?

Answer 80

Males and females ages 9-45

Question 81

What is seen on a positive FA test for measles?

Answer 81

Multinucleated giant cells.