Herpes and VZV Overview Quiz

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Questions and Answers

Which characteristic is shared by both HSV-1 and HSV-2?

50% DNA homology. (correct)

Primarily causing disease below the waist.

Latent infections of fibroblast cells.

Predominantly lytic infections of neurons.

How is HSV-1 typically transmitted?

Through oral contact or saliva-contaminated items. (correct)

During vaginal delivery from mother to infant.

Through sexual contact.

Via autoinoculation.

Which of the following is a typical manifestation of a herpes simplex virus lesion?

A clear vesicle on an erythematous base. (correct)

A dark, hard nodule with a clear base.

A deep, scarred tissue with a pustular border.

A white plaque on an erythematous base.

What type of cells does HSV-1 and HSV-2 typically infect at the entry site, causing lysis?

Fibroblast and epithelial cells. Signup and view all the answers

Which condition is most often associated with HSV-2 transmission during birth?

Neonatal infection with dissemination to multiple organs. Signup and view all the answers

Which of the following diagnostic methods is most useful for identifying a primary HSV infection?

Serology. Signup and view all the answers

What is the primary mechanism of action of nucleoside analog drugs like acyclovir in treating HSV infection?

Inhibiting viral DNA synthesis. Signup and view all the answers

Where does HSV-1 typically establish latency after initial infection?

Trigeminal ganglia. Signup and view all the answers

What is the primary method by which Varicella-Zoster Virus (VZV) reactivates?

Through anterograde travel towards nerve endings from the sensory ganglia Signup and view all the answers

Which of the following best describes the effectiveness of nucleoside analogs against VZV?

They are effective at reducing fever and skin lesions if treatment starts within 3 days of infection onset, before lesions. Signup and view all the answers

Which clinical manifestation is associated with the reactivation of Varicella-Zoster Virus (VZV)?

Vesicular rash along a specific dermatome. Signup and view all the answers

How is Varicella-Zoster Virus (VZV) diagnosed from skin lesions?

Genome detection in clinical specimens. Signup and view all the answers

What is a common characteristic of the rash associated with VZV reactivation (shingles)?

It is localized to a single dermatome and often painful. Signup and view all the answers

What specific characteristic of Varicella-Zoster Virus (VZV) is not addressed by common antiviral drugs?

The virus in its latent state. Signup and view all the answers

What is a key mechanism of VZV that leads to the formation of a dermatomal rash during reactivation?

Formation of multinucleated giant cells (polykaryocytes) in skin cells. Signup and view all the answers

Which of the following HPV vaccine types targets the most HPV types?

9-valent vaccine (Gardasil 9) Signup and view all the answers

What is the primary function of the L1 protein in HPV vaccines?

To form empty shells that resemble HPV viruses, triggering an immune response Signup and view all the answers

Which of the following is NOT a way that VZV virus can be detected?

Through blood culture. Signup and view all the answers

Which of the following is NOT a recommended screening test for cervical cancer?

Blood test for HPV antibodies Signup and view all the answers

What is the main characteristic of a koilocyte cell as observed in a Pap smear?

An enlarged cell with a clear halo around a shrunken nucleus Signup and view all the answers

Which of the following treatment methods is NOT typically used for the removal of HPV-related warts or precancerous lesions?

Antibiotics Signup and view all the answers

What is the typical seroprevalence rate of Cytomegalovirus (CMV) in adults?

50-90% Signup and view all the answers

Which of the following is NOT a target cell for CMV infection?

Neurons Signup and view all the answers

In which cells does CMV typically remain latent?

Myeloid stem cells Signup and view all the answers

What are the potential severe disease outcomes of primary CMV infection or reactivation in immunocompromised individuals?

Interstitial pneumonia, gastroenteritis, and retinitis. Signup and view all the answers

Which of these is NOT a mode of horizontal transmission of CMV?

Transplacental Signup and view all the answers

Which of the following is a route of vertical transmission of CMV?

Transplacental transmission Signup and view all the answers

Which of the following is NOT a typical sign of congenital CMV infection?

Elevated blood pressure Signup and view all the answers

When is the risk for birth defects highest in infants with congenital CMV?

When mothers had primary CMV infections during their pregnancies. Signup and view all the answers

Which of the following is NOT a common organ system affected by Cytomegalovirus (CMV) in immunocompromised individuals?

Pancreas Signup and view all the answers

Why is viral isolation in fibroblast cell cultures not a suitable method for rapid CMV diagnosis?

The cytopathic effect develops slowly, requiring weeks Signup and view all the answers

Which diagnostic method is most useful for detecting congenital CMV infection?

Molecular diagnosis using PCR Signup and view all the answers

Why is serology not always dependable for diagnosing CMV infection in immunocompromised patients?

IgM levels can rise even during CMV reactivation, not just primary infection Signup and view all the answers

Which of the following antiviral drugs is NOT specifically mentioned for the treatment of CMV infections?

Acyclovir Signup and view all the answers

Which of the following is a hallmark feature of Epstein-Barr Virus (EBV) infection?

Seropositivity is high in adults, with intermittent shedding Signup and view all the answers

What is the primary route of transmission for Epstein-Barr Virus (EBV)?

Saliva (oral route) Signup and view all the answers

What is a key mechanism by which EBV establishes infection in B cells?

Immortalisation Signup and view all the answers

What is the primary target cell for HHV-8?

B cells Signup and view all the answers

Which condition is NOT associated with HHV-8 infection?

Cervical cancer Signup and view all the answers

What type of papillomavirus is primarily responsible for cervical cancer?

High-risk genital HPVs Signup and view all the answers

Which statement about HPV-related lesions screening is true?

Pre-cancerous lesions can be treated to prevent cancer. Signup and view all the answers

What is a characteristic of genital HPV infections?

Usually transient and clear within 3 years Signup and view all the answers

Which HPV types are primarily associated with respiratory papillomatosis?

HPV 6 and 11 Signup and view all the answers

What role do the E6 and E7 proteins play in HPV infections?

They upregulate growth by targeting p53 and pRB pathways. Signup and view all the answers

Which of the following is a method of definitive HPV diagnosis?

PCR and real-time PCR analysis Signup and view all the answers

What are the symptoms of condyloma acuminata due to HPV infections?

Numerous warts in genital and anal areas Signup and view all the answers

What is the primary method to diagnose cutaneous HPV infections?

Wart appearance Signup and view all the answers

Study Notes

Herpesviridae

Genome: linear double-stranded DNA
Icosahedral capsid with 162 capsomers, surrounded by an amorphous tegument
Spherical to pleomorphic envelope (150-200 nm in diameter)

Herpesviridae Subfamilies and Viruses

Alphaherpesvirinae:
- HHV-1 (Herpes simplex type 1): mucoepithelial cells and neurons; spread via close contact (STD)
- HHV-2 (Herpes simplex type 2): mucoepithelial cells and neurons; spread via close contact (STD)
- HHV-3 (Varicella-zoster virus): mucoepithelial and T cells and neurons; spread via respiratory and close contact
Betaherpesvirinae:
- HHV-5 (Cytomegalovirus): monocytes, granulocytes, lymphocytes, and epithelial cells; myeloid stem cell; spread via close contact (STD), transfusions, tissue transplant, and congenital
- HHV-6: lymphocytes and T cells; spread via saliva
- HHV-7 : like HHV-6, spread via saliva
Gammaherpesvirinae:
- HHV-4 (Epstein-Barr virus): B cells and epithelial cells; spread via saliva (kissing disease)
- HHV-8 (Kaposi's sarcoma-associated virus): lymphocytes and other cells; spread via saliva (possibly blood exposure)

Herpesvirus Replication

Attachment to host receptors mediates endocytosis
Fusion with plasma membrane releases nucleocapsid and tegument proteins into cytoplasm
Capsid transported to nuclear pore; viral DNA released into nucleus
Transcription/translation of immediate early genes (regulate gene transcription)
Replication of parental genome via rolling circle mechanism
Transcription/translation of late mRNAs (structural proteins)
Assembly in nuclear factories; budding through modified nuclear membrane
Release at plasma membrane (lytic replication)

Latent Replication

Viral DNA takes circular (episomal) structure
Generates latency-associated transcripts (LATs) instead of translating into proteins; inhibits important immediate early genes.

Herpes Simplex Virus (HSV) Type 1 and 2

HSV-1 and HSV-2 share characteristics (50% DNA homology)
HSV-1 typically spreads via oral contact or saliva-contaminated items, while HSV-2 is primarily spread through sexual contact or from an infected mother to infant at birth.
Neonatal HSV infection is often severe and potentially fatal.

Diagnosis and Therapy of HSV Infection

Diagnosis: Viral isolation from lesions, detection of viral genome (vesicle, tissue), serology (limited use).
Therapy: Nucleoside analogs (acyclovir, valacyclovir, famciclovir) inhibit viral DNA synthesis; shorten symptoms; doesn't affect latent virus

Varicella-Zoster Virus (VZV)

Primary infection (chickenpox) associated with mild febrile illness and generalized vesicular rash
VZV establishes a latent infection within sensory ganglia
Reactivation (shingles) causes vesicular rash along the entire dermatome, very painful post-herpetic neuralgia

Cytomegalovirus (CMV)

Ubiquitous; prevalent in children and adults (10-15% of children before age 5, 50-90% seroprevalence in adults).
Horizontal transmission through organ transplantation; contact with bodily secretions (saliva, tears, urine, semen, stool, vaginal/cervical secretions)
Vertical transmission through transplacental transmission, breastfeeding (maternal milk or colostrum).
Severe disease can result from primary infection or reactivation in immunocompromised hosts; can cause interstitial pneumonia, gastroenteritis, retinitis, organ transplant rejection, death.
CMV is a leading cause of congenital disease: microcephaly, intracerebral calcification, jaundice, hepatosplenomegaly, rash, vision or hearing loss, and mental retardation
In immunocompromised subjects, CMV can affect almost every organ (liver, lungs, central nervous system, gastrointestinal tract, kidneys, and eyes)

Epstein-Barr Virus (EBV)

Ubiquitous (80-90% seropositive adults)
Primarily spread through saliva.
Infections of epithelial cells of the oropharynx and nasopharynx; B-cells.
EBV can cause lytic infections of epithelial cells and latent infections or immortalization of B cells.
Acute infection can cause infectious mononucleosis (kissing disease).
Symptoms: Pharyngitis, swollen lymph nodes, enlarged spleen, exudative pharyngitis, high fever, malaise.
Associated with different cancers (endemic Burkitt lymphoma, Hodgkin disease, nasopharyngeal carcinoma, B-cell lymphomas).
Diagnosis is usually serological (Paul-Bunnel test, EBV-specific serologic tests)

Other Human Herpesviruses, HHV-6, HHV-7

HHV-6 (HHV-6A and HHV-6B) cause exanthem subitum (roseola) in young children (ages 6-24 months)
Rapid onset of high fever, followed by rash on the trunk and face.
Can reactivate in transplant patients, associated with MS and chronic fatigue syndrome

Other Human Herpesvirus, HHV-8

Member of the X-Herpesvirinae
Associated with Kaposi's sarcoma (KS), primary effusion lymphoma (a rare type of B-cell lymphoma, and multicentric Castleman disease).
B cells are the primary targets, but limited number of endothelial, monocyte, and epithelial cells are also affected.
More prevalent in some geographic areas (Italy, Greece, Africa) and those with HIV/AIDS, likely spread sexually or through blood exposure.

Papillomaviridae

Genome: double-stranded DNA, circular
Icosahedral capsid (50-55 nm)
Nonenveloped virus
100 genotypes, classified by tissue tropism
Cutaneous HPVs cause warts (on skin).
Mucosal HPVs cause papillomas and condylomas (on mucous membranes)
Some types cause benign tumors, others cause carcinomas (e.g., cervical cancer)
E6 and E7 (proteins) promote unregulated growth.
The basal cell layer is a portal of entry via breaks in the skin.
Cutaneous syndromes: warts, epidermodysplasia verruciformis (EV)
Mucosal syndromes: papillomatosis, condyloma acuminata.
HPV causes six types of cancer, including cervical, vulvar, vaginal, oropharyngeal, anal and penile.
The infection is typically transient, but long-term high-risk HPV persistence is the most important predictor of cervical cancer.
HPV testing, visual inspection (VIA), and conventional Pap test (cytology) are important methods of screening for HPV-related lesions.

HPV Infection Treatment

Removal of warts and precancerous lesions (e.g., with salicylic acid, liquid nitrogen, laser or surgical removal)
Immune modifiers (e.g., interferon, imiquimod) boost the immune system.

HPV vaccines are prepared using virus-like particles (VLPs)
Three available vaccines: quadrivalent (Gardasil), 9-valent (Gardasil 9), bivalent (Cervarix).
Vaccination is initially recommended at age 11 or 12 for both boys and girls.
Continued cervical cancer screening is recommended.

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Description

Test your knowledge on herpes simplex viruses (HSV-1 and HSV-2) and Varicella-Zoster Virus (VZV) with this quiz. Covering transmission methods, symptoms, diagnostics, and treatment mechanisms, this quiz will help reinforce key concepts about these common viruses. Perfect for students studying virology or infectious diseases.