19B - SEROLOGICAL AND MOLECULAR DETECTION OF VIRAL INFECTIONS: OTHER VIRAL INFECTIONS

Herpes Simplex Virus

Large, complex, and enveloped DNA viruses

Herpes Simplex Virus

Capable of establishing latency

Capable of being dormant in a susceptible host after the primary infection

Lifelong persistence in the host

Herpes Simplex Virus 1

Herpes Simplex Virus

Oral herpes

Herpes Simplex Virus 2

Herpes Simplex Virus

genital herpes

Varicella-Zoster Virus (VZV)

Herpes Simplex Virus

chickenpox and shingles

Epstein-Barr Virus (EBV)

Herpes Simplex Virus

infectious mononucleosis

Cytomegalovirus (CMV)

Herpes Simplex Virus

infectious mononucleosis-like disease

Human Herpes Virus-6 (HHV-6)

Human Herpes Virus-7 (HHV-7)

Herpes Simplex Virus

6th childhood disease

Human Herpes Virus-8 (HHV-8)

Herpes Simplex Virus

Kaposi sarcoma

Epstein-Barr Virus

Mostly transmitted through salivary secretions from an infected individual

Can also be transmitted by transfusion, bone marrow transplant, tissue grafts, sexual contact, perinatal exposure, etc.

Kissing Disease

Epstein-Barr Virus

Other name

childhood

asymptomatic

mild

Epstein-Barr Virus

EBV infections usually occur during _

Infections are _ and _ in infants and young children

infectious mononucleosis (IM)

Epstein-Barr Virus

Primary infections in adolescents and adults are more associated with _ _

Fever, lymphadenopathy, and sore throat

Epstein-Barr Virus

Three classic S/S

Burkitt’s lymphoma

Hodgkin disease

Epstein-Barr Virus

EBV can be associated with different malignancies (2)

oropharynx

epithelial cells

B lymphocyte

Epstein-Barr Virus

Infections starts in the _ and primarily infects _ _ and _ _

beta-integrins

Epstein-Barr Virus

EBV binds to _-_ present in the EC which initial viral infection occurs

lytic cycle

Epstein-Barr Virus

Initial viral replication is signaled by the _ _ of the virus:

Viral replication

Lysis of host cells

Release of infectious virions to adjacent cells/organs

Epstein-Barr Virus

Initial viral replication is signaled by the lytic cell of the virus (3)

B lymphocytes

Epstein-Barr Virus

EBV infects the _ _ which spreads the virus throughout the lymphoreticular system

CD21

Epstein-Barr Virus

EBV enters the B lymphocytes through _

EBV specific antibodies

Heterophile antibodies

Autoantibodies

Epstein-Barr Virus

The infected B lymphocytes are polyclonally activated which produces: (3)

Early antigens (EA)

Late antigens

Latent antigens

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection (3)

Early antigens

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

produced during initial stages of viral classification

EA-D

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

Early antigens: Diffuse distribution in the nucleus and cytoplasm

EA-R

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

Early antigens: Restricted in the cytoplasm only

Late antigens

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

appear during the lytic cycle after viral DNA synthesis inside the infected cell

Viral capsid antigens

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

Late antigens: Present in the protein capsid

Membrane proteins

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

Late antigens: Present in the viral envelope

Latent antigens

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

appear during the latent phase of infection

EBV nuclear antigens 1-6

Latent membrane proteins 1, 2A, 2B

Epstein-Barr Virus

EBV antigens can be differentiated into the different phases of infection:

Latent antigens (2)

Heterophile Antibodies

Epstein-Barr Virus

Antibodies that are capable of reacting with similar antigens from unrelated species

IgM

polyclonal B-cell

Epstein-Barr Virus

Heterophile Antibodies

EBV Heterophile Abs are _ antibodies that are produced due to _ _-_ activation

3

Epstein-Barr Virus

Heterophile Antibodies

EBV Heterophile Abs are IgM antibodies that are produced due to polyclonal B-cell activation

Decrease after _ months of infection

Primary immune response

horse

sheep

bovine

Epstein-Barr Virus

Heterophile Antibodies

EBV Heterophile Abs react with _, _, and _ RBCs

40

80-90

Epstein-Barr Virus

Heterophile Antibodies

Produced by _% of patients during the first week of disease and _-_% by the third week of infections

Monospot Test

Epstein-Barr Virus

Heterophile Antibodies

Used to distinguish the heterophile Ab of IM from other heterophile Abs

guinea pig kidney

Epstein-Barr Virus

Heterophile Antibodies

Monospot Test

Serum premixed with _ _ _ antigens is still capable of agglutinating horse RBCs

beef erythrocyte antigens

Epstein-Barr Virus

Heterophile Antibodies

Monospot Test

Serum premixed with _ _ _ are not capable of agglutinating horse RBCs

Indirect Immunofluorescence Assay

Epstein-Barr Virus

Laboratory Diagnosis of EBV

gold standard for EBV serology methods

IgM anti-VCA

Epstein-Barr Virus

Laboratory Diagnosis of EBV

most useful marker for acute IM

IgG anti-VCA

Epstein-Barr Virus

Laboratory Diagnosis of EBV

present at the onset of IM but persists for life

Anti-EA-D

Epstein-Barr Virus

Laboratory Diagnosis of EBV

seen during acute IM

Anti-EBNA

Epstein-Barr Virus

Laboratory Diagnosis of EBV

Appears during convalescence

Longest to appear

Cytomegalovirus

Spread through close, and prolonged contact with infectious body secretions

Cytomegalovirus

Most common cause of congenital infections

IM-like illness

Cytomegalovirus

Primary infections are asymptomatic but a small percentage experience _-_ _

graft rejection

Cytomegalovirus

Clinical manifestations are more serious in immunocompromised patients, especially in organ-transplant patients

CMV (+) can increase risk for _ _

Varicella-Zoster Virus

Causative agent of varicella and herpes zoster

Varicella

Varicella-Zoster Virus

highly contagious illness with a blister-like rash with intense itching and fever; primary infection (bulutong)

Herpes Zoster

Varicella-Zoster Virus

reactivation of VZV, more localized and painful

inhalation

Varicella-Zoster Virus

Transmitted through _ of respiratory secretions or aerosols from skin lesions

lesions

Varicella-Zoster Virus

Diagnosis of VZV is based on identifying the _ associated with infection

dorsal root/autonomic ganglia

Varicella-Zoster Virus

VZV travels from the skin lesions to the blood and eventually to its place of latency, the _ _/_ _

15-30

Varicella-Zoster Virus

Reactivation of VZV occurs in _-_% of persons with a history of varicella

Tzanck cells

Varicella-Zoster Virus

_ _ are multinucleated giant cells associated with VZV which can be found in smears from the lesions

This method does not differentiate VZV and HSV

qPCR

Varicella-Zoster Virus

method of choice for diagnosing VZV

IgM anti-VZV

Varicella-Zoster Virus

Serologic testing with VZV is not usually performed

_ _-_ may not be detectable until the convalescent stage of infection

four-fold

Total (IgG) anti-VZV

Varicella-Zoster Virus

Serologic testing with VZV is not usually performed

Accurate serologic testing relies on the _-_ rise between parallel samples

Most serologic tests detect _ _-_

Rubella

Single stranded, enveloped RNA virus (1)

Togaviridae

Rubella

Belongs to the family _

German measles/3-day measles

Rubella

Disease caused (2)

unvaccinated

Rubella

Common in young, _ adults

rash

Rubella

Produces a characteristic _ that appears first on the face, then to the trunk and extremities

ELISA

Rubella

Serology tests using _ is the most common method of diagnosis for Rubella

rubella-specific IgM

Rubella

Primary rubella infections are associated with a _-_ _ antibodies or four-fold rise in antibody titers

Rubeola

Single stranded, enveloped RNA virus (2)

Paramyxoviridae

Rubeola

Belongs to the family _

Serologic testing

Rubeola

_ _ is the most practical and reliable means of diagnosis

10-14

Rubeola

Infection can be established by the presence of rubeola-specific IgM or a four-fold rise between rubeola-specific IgG titers

_-_ days between acute and convalescent phase

Measles

Highly contagious infection that is spread through aerosol droplets

cough, coryza, and conjunctivitis

Measles

Produces prodromal S/S of _,_, & _

Appears before the onset of the main clinical manifestation

Koplik spots

Measles

lesions on the oral mucosa consisting of irregular red spots with a bluish-white speck in the center

14

Measles

The typical rash of measles appear about _ days of exposure and usually begins on the hairline

Mumps

Single stranded, enveloped RNA virus (3)

Paramyxoviridae

Mumps

Belongs to the family _

respiratory droplets, saliva, and fomites

Mumps

Transmitted by infected _, _, & _

parotitis

Mumps

Causes _

laboratory testing

MMR Serology

Although the diagnosis of rubella, measles, and mumps is usually based on clinical findings, _ _ may be helpful in confirmation

Current infections

MMR Serology

indicated by the presence of IgM antibodies specific for the appropriate virus or by a four-fold rise in virus-specific IgG antibodies in two separate specimens collected during the acute and convalescent phases of disease

Testing for IgG antibodies

MMR Serology

most commonly performed to screen for immunity to these viruses

RT-PCR

MMR Serology

useful adjunct to serology in detecting viral RNA in patients with inconclusive serology results, in epidemiological studies, and in the detection of congenital rubella infections

MMR Vaccine

Part of the routine immunization schedule of infants and children

Live attenuated vaccine

MMR Vaccine

What type?

12-15 months old

MMR Vaccine

1st dose

4-6 y/o

MMR Vaccine

2nd dose

Uninfected

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (-) IgG

• (-) IgA

Anti-EA

• (-) EA-D

• (-) EA-R

• (-) Anti-EBNA

• (-) Heterophile Antibody (IgM)

Acute IM

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (+) IgM

• (++) IgG

• (±) IgA

Anti-EA

• (+) EA-D

• (-) EA-R

• (-) Anti-EBNA

• (±) Heterophile Antibody (IgM)

Convalescent IM

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (+) IgG

• (-) IgA

Anti-EA

• (-) EA-D

• (±) EA-R

• (+) Anti-EBNA

• (±) Heterophile Antibody (IgM)

Past infection IM

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (+) IgG

• (-) IgA

Anti-EA

• (-) EA-D

• (-) EA-R

• (+) Anti-EBNA

• (-) Heterophile Antibody (IgM)

Chronic active infection IM

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (+++) IgG

• (±) IgA

Anti-EA

• (+) EA-D

• (++) EA-R

• (±) Anti-EBNA

• (-) Heterophile Antibody (IgM)

Post-transplant lymphoproliferative disease

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (++) IgG

• (±) IgA

Anti-EA

• (+) EA-D

• (+) EA-R

• (±) Anti-EBNA

• (-) Heterophile Antibody (IgM)

Burkitt’s lymphoma

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (+++) IgG

• (-) IgA

Anti-EA

• (±) EA-D

• (++) EA-R

• (+) Anti-EBNA

• (-) Heterophile Antibody (IgM)

Nasopharyngeal carcinoma

Serological Responses of Patients With Epstein-Barr Virus-Associated Diseases

Anti-VCA

• (-) IgM

• (+++) IgG

• (+) IgA

Anti-EA

• (++) EA-D

• (±) EA-R

• (+) Anti-EBNA

• (-) Heterophile Antibody (IgM)