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Flashcards in Herpesviruses Deck (121):
1

Alpha Herpesviruses

Herpesvirus 1, 2, 3

1&2 = HSV

3= VZV

2

Gamma Herpesviruses

#4 = EBV

 

**also #8?

3

Beta Herpesvirinae

Herpesvirus 5, 6, 7

5 = CMV

6 = HHV6

7 = HHV7

4

Herpesvirus genome and structure

dsDNA genome

-Envelope, tegument, and capsid

-Glycoprotein spikes

5

Herpesvirus produces proteins in what three phases

  1. Immediate Early proteins (alpha) regulate gene transcription
  2. Early proteins (Beta) DNA pol and TF's
  3. Late Proteins (Gamma) = structural proteins

6

Herpesvirus envelope is from ______

 

the nucleus

7

Herpesvirus encodes what two enzymes

 

DNA-dependent DNApol

Thymidine Kinase

8

80% of Herpesvirus are ______

 

asymptomatic

9

Oral herpes (acute gingivostomatitis) incubation time

 

One week

10

Cold sores =

 

herpes labialis

11

Herpes labialis prevalence?

20-40%

12

Herpes Keratitis most frequent cause of ______

 

blindness

13

Major signs of herpes keratitis

 

  • Unilateral red eye
  • Vesicular skin rash
  • Folicular conjunctivitis
  • DENDRITIC CORNEAL ULCER (= hallmark sign)

14

Herpes keratitis Tx

 

Acyclovir cream 3%

15

Herpes Whitlow caused by

 

HSV 1 or 2

16

Herpes whitlow incubation period

 

2-20 days

17

Herpes whitlow infection characteristics (3)

Fever

Malaise

Treatmtent is SELF LIMITING

18

Herpes gladiatorum appearance and treatment

Head and neck blister cluster

Treatment is acyclovir

19

Eczema herpeticum epid, features, incubation, and Tx

 

  • Rare, usually children
  • Severe disseminated disease at pre-existing sites of skin damage
  • Incubation of 5-12 days
  • Tx = Acyclovir and ANTIBIOTICS to prevent 2' infection

20

Genital Herpes systemic effects

 

Fever, flu-like symptoms, swollen lymph nodes

21

Genital HSV2 lasts about _______

 

one month

22

HSV encephalitis usually caused by

 

HSV1

23

HSV accounts for __% of all encephalitic viral infections

 

10-20%

24

HSV encephalitis phases

 

Prodrome = fever and nausea

Encephalopathy = either acute or subacute

25

HSV encephalitis has a predilection for edema and hemorrhage in ______

 

temporal lobe

26

CSF appearance in HSV encephalitis

 

Glucose and protein = mostly normal

Elevated WBC (mostly lymphocytes)

RBC found becaue of hemorrhage

27

HSV meningitis mostly caused by ____

HSV2

28

50% of HSV meningitis cases are _____ and 50% are _____

Primary and Secondary

29

HSV enceph vs. meningitis -- CSF appearance

 

Enceph has way higher RBC

Meningitis has higher WBC and Protein

30

Neonatal herpes caused mostly by

HSV2

31

Neonatal HSV can be transmitted...

 

  1. vertically from mom
  2. from another neonate

32

Symptoms of neonatal HSV (after vs before birth infections)

After Birth = Many confined to skin, eye, and mouth. Encephalitis in 35%. Disseminated in 25%.

 

Before birth = Premature birth, low birthweight, microcephaly, hydrocephalus, chorioretinitis, vesicular skin lesions

33

  • HSV replicates in ______ cells.
  • Hangs out in the ______ and______ ganglia.
  • Establishes ________

 

  • epithelial
  • trigeminal and sacral
  • latency

34

HSV1 and 2 cause 3 types of infections:

 

  1. Lytic (replication in mucoepithelial cells, disease @ lesion site)
  2. Latent (neuronal)
  3. Persistent (in lymphocytes and MQ

35

Cell death during HSV infection can result from _____, _____, or _______

 

  1. Virus induced inhibition of cell molecules
  2. DNA degradation
  3. Cytoskeleton disruption

36

Other cellular hallmarks of HSV infection

 

  • COWDRY bodies (acidophilic intranuclear inclusion)
  • Syncitia

37

Innate ___________ may be sufficient to limit HSV infection

innate protection by interferon

38

Antivirals for HSV

 

  • Anything ending in "cyclovir" (A, Pen, Val, Fam)
  • Adenosine Arabinoside
  • Iodo-deoxyuridine
  • Trifluridine

39

Varicella is a result of _______ infection of VZV

 

primary

40

Varicella Pox appearance

 

vesicle, pustule, crust, scabbed lesions

Lesions appear for 3-5 days

41

Varicella incubation period

 

about 2 weeks

42

When is chickenpox contagious?

 

2-3 days before rash appears

43

__________ can be observed during the course of chickenpox infection

 

ALL stages of lesions

44

Varicella rash characteristics and associated diseases?

 

  • more prevalent on trunk
  • SCALP presence distinguishes it from other rashes
  • May cause Interstitial PNA in 20-30% of adults (from inflammatory rxn at site of lesion)

45

Herpes Zoster is a _______ infection of __________ Varicella

 

recurrent infection of latent VZV

46

Shingle rash is usually ________ and forms a __________

unilateral

forms a "dermatomal pattern"

47

VZV transmission via ________, rarely _____

Inhalation

Rarely transplacental

48

VZV initially infects the _________ and spreads to ________ by VIREMIA

 

respiratory tract

RE system

49

Syncitia and intracellular inclusions occur in VZV because the virus...

 

is spread cell to cell

50

VZV is latent isn _________ or __________

 

DRG or Cranial nerve ganglia

51

Who is given VZV immunoglobulin? (3)

 

  • IC patients
  • Exposed staff
  • neonates from infected mothers

 

52

VZV vaccine = _______

Live attenuated

53

VZV vax can be effective when given...

post exposure

(antibodies and CMI are stimulated)

54

VZV vaccination in adults is an effective means to...

 

boost antibodies to reduce onset of zoster

55

Epstein Barr Virus: Family/Herpesvirus type

Gammaherpesvirinae

(HHV-4)

56

EBV genomem, shape, and surface proteins

 

dsDNA

icosahedral


gp350/220 + gp110

57

EBV gp350 surface protein forms _________, and binds to _____ receptor on B cells

Glycoprotein complex I

CD21 (CR2) on B cells

58

EBV internalization occurs by ______

Cytoplasmic vesicles

59

Three potential outcomes for EBV infection

 

  1. Replicate in B cells or epithelial cells
  2. latent infection of B cells
  3. Stimulate and immortalize B cells

60

EBV transcription and translation start with _________ genes

 

Immediate-Early

61

Two types of EBV cellular infections

  1. Permissive (Epithelial and B cell)
  2. Nonpermissive (B cell)

62

Viral capsid and glycoproteins that are synthesized by EBV (3) during a Permissive Epithial & B cell infection

 

  1. Early antigen (EA)
  2. Viral Capsid Antigen (VCA)
  3. Glycoproteins of the membrane antigen (MA)

63

EBV: Three viral genes that are expresed depending on the state of the B cell

 

**This is part of what type of B cell infection??**

  1. EBNA's  = E-B nuclear antigens
  2. LMP's = Latent membrane proteins
  3. LP's = Latent proteins

 

**Non-permissive B cell infection**

64

What are EBNA's and LP's?

DNA binding proteins

 

establish and maintain infection

65

What are LMP's?

Membrane proteins with oncogenic-like activity

(stimulate and immortalize B cell)

66

EBV establishes latency in _________

Memory B cells in which only the EBNA and LMP are expressed

67

Purpose of the DNA binding protiens and LMPs (overall)

 

maintaining the genome in the B cells but minimizing chance of immune recognition of the infected cells

68

Permissive epithelial and B cell infection results in ____________

 

Heterophile Antibody-Positive Infectious Mononucleosis (Mono)

69

Sx of infectious mononucleosis

 

lymphadenopathy, splenomegaly

exudative pharyngitis (w HIGH FEVER)

70

Serious complications with mono:

 

  • Laryngeal obstruction or splenic rupture
  • Meningoencephalitis

 

71

Anti EA and Anti VCA antobidies occur within __________, while anti EBNA antibodies are formed at about __________

 

One week

 

2 months

72

EBV incubation period is roughly _________

 

2 months

73

3 diseases from Non-Permissive B cell infection:

 

  1. EBV-induced Lymphoproliferative Disease
  2. Burkitt's Lymphoma
  3. Nasopharyngeal Carcinoma

74

EBV induced Lymphoproliferative disease characteristics (3)

(CBC, immune response, and who is most likely to get it)

 

  • High B cell lymphocytes
  • Lack of T cell response d/t immunosuppressive drugs
  • occur at higher rates in heart and lung transplant patients than those getting bone marrow or kidney/liver

75

Burkitt's lymphoma definition =

Agressive monoclonal B cell lymphoma of the jaw and face

 

Affects children, associated with HIV (AIDS-associated malignancy)

76

NP carcinoma endemic in ______.

Proliferation of _______ cells.

Symptoms?

 

  • Asia + N. Africa
  • Epithelial cells
  • Nasal discharge, nosebleed, PT tube obstruction, Metastasis to other organs

77

EBV transmitted by (3)

 

saliva, oral contact, fomites

78

Clinically, EBV causes _____ or ______ infections

 

Acute or latent

79

Acute EBV infection pathogenesis (three steps)

 

replication in NP cells

spread to Salivary gland

VIREMIA and infection of RE system

80

EBV latent infection:

1. Virus is present as _____ in B cell and epithelial cells.

2. Viral ______ rate is low

3. What cellular interaction causes this to occur?

 

  • Episome
  • reactivation rate is low
  • happens from NP cells infecting passing B cells

81

B cell proliferation in EBV infection causes increase in __________

 

heterophile antibody

82

T cell activation during EBV infection results in __________

 

atypical lymphocytes called DOWNEY CELLS

 

****************

83

What is a Downey Cell?

 

large lymphocye due to antigen stimulation

Have basophilic cytoplasmic rim

84

Heterophile antibody results from activation of _________

When can it be detected/how long does it last?

B cells

detected at 1st week, can last several months

85

Heterophile is a great indication for whom?

 

Adults (not reliable in children)

86

What is a Paul and Bunnel test?

 

MonoSpot test

detects Antibodies that cause agglutination of RBC's from another species (horse)

87

___% of adults have been infected with EBV by age 40

 

95%

88

Infants are susceptible to EBV when?

 

When mom's antibody protection wears off

89

EBV diagnostic tests (4)

 

  1. Physical exam (look at SPLEEN)
  2. CBC/CMP
  3. MonoSpot test
  4. Microscopy for Downey Cells

90

Explain the blood test to determine the stage of EBV infection.

(4 stages)

  1. No VCA antibodies = susceptible
  2. IgM to VBA but no EBNA = Primary infection
  3. VCA and EBNA antibodies = Past infection
  4. Elevation of antibodies to EA in presence of EBNA antibodies = REACTIVATION

91

CMV family member (and class)

 

HHV5

Betaherpesvirinae

92

Three infections from CMV

  1. Congenital CMV
  2. Heterophile-negative mononucleosis
  3. Diseases of Immunocompromised patients

93

Congenital CMV: _____ infection from mom is spread to placenta.

_______ infection in mom rarely causes congenital abnormalities

Primary

Reactivation

94

CMV may cause ________ or ________ symptoms

 

Give some examples of both.

 

Temporary (liver, spleen, lung, seizure)

Permanent (Hearing/vision loss, Microcephaly, Mental disability)

95

Heterophile-negative mono is similar to IM except for...

Paul-Bunnell test is negative

96

CMV diseases in immunocompromised patients include

 

pneumonia

gastroenteritis

RETINITIS

encephalitis

97

CMV cellular hallmark

 

Cowdry bodies

98

What are Cowdry bodies?

 

giant multinucleated cells in CMV infection

found in Parotid gland

 

OWLS EYE appearance

99

CMV causes ______ infection in salivary, breasts, kidneys, and peripheral blood leukocutes.

This leads to _____________

Persistent infection

Leads to chronic excretion by the organ involved.

100

CMV incubation period

 

4-6 weeks

101

CMV main sites of replication

 

Salivary glands and Kidneys

102

CMV control

no treatments,

drugs possess many sides

Drugs = Ganciclovir, valganciclovir,

Foscarnet, cidofovir

103

HHV6 and HHV7, also known as...

 

Betaherpesvirinae (roseolovirus)

104

HHV6 infects what cells? Where does it replicate

 

lymphocytes, monocytes, epithelial and endothelial cells

Replicates in salivary glands

 

****These are both similar to CMV****

105

Roseola (6th disease) due to ____ more than ______

HHV6 more than HHV7

106

Roseola is a common _____________ disease affecting _____

 

acute febrile

infants

107

When/where does Roseola rash appear?

 

After three days (after fever)

appears on neck, trunk, thighs

108

_____ infections of Roseola (HHV6) can cause other complications, such as...

 

What about IC patients?

 

Primary infections can cause encephalitis, lymphadenopathy, and hepatitis

 

**May cause these things in Immunocompromised patients upon reactivation.

109

Another name for infantile Roseola

 

Exanthem subitum

110

Infection with HHV6 and 7 occur mainly during ________

childhood

111

Seroprevalence of HHV6 in 2 year olds approaches...

 

80%

112

HHV7 antibody prevalence in adults reaches ____%

98%

113

What is HHV8

 

Kaposi's Sarcoma-associated Herpes

114

HHV8 causes ____ or _______ infections

 

It infects ____________ cells but multiplies in ________ cells

latent or lytic

 

Infects peripheral blood lymphocytes but multiplies in endo/epithelial cells and monocytes

115

Kaposi's sarcoma is a ___ tumor form ______ lineage

 

spindle cell tumor derived from endothelial cell lineage

116

Kaposi Sarcoma locations

 

under skin, in oral lining, nose, and throat

117

Kaposi sarcoma can be limited to _____ or may...

 

mucocutaneous lesions or may spread to other otgans

118

Kaposi sarcoma cancer spreads to ___ or ____ causing bleeding and function issues

 

GI or lungs

119

HHV8 is a defining illness for what?

 

HIV/AIDS

120

HHV8 may be spread via what routes?

 

Sexual or Nonsexual

nonsexual = poorly understood

121

HHV8 treatments (2)

 

  1. Tumor surgical excision
  2. Irradiation