Herpesvirus Infections Overview

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Questions and Answers

What are the three stages of pathogenesis for herpesvirus infections?

Primary infection, latency, and reactivation.

What type of genetic material does a herpesvirus contain?

Linear double-stranded DNA.

What is the term for a recurrent infection with asymptomatic viral shedding or clinical manifestations?

Recrudescence.

What is associated with the risk of rapid and widespread cutaneous dissemination of HSV infection in patients with atopic dermatitis?

Mutations in the gene encoding filaggrin. Signup and view all the answers

Besides atopic dermatitis, what other conditions may cause an impaired skin barrier which might lead to a similar presentation of widespread HSV infection?

Burns, irritant contact dermatitis, pemphigus, Darier disease, Hailey–Hailey disease, mycosis fungoides, and Sézary. Signup and view all the answers

Besides HSV-1, what is another common cause of herpetic whitlow in adolescents and adults?

HSV-2 Signup and view all the answers

What is the most common cause of herpes gladiatorum?

HSV-1 Signup and view all the answers

What is the typical appearance of herpes simplex folliculitis lesions?

Follicular vesicles and pustules Signup and view all the answers

What is a common cause of a herpetic sycosis in a man's beard area?

Shaving with a blade razor Signup and view all the answers

Besides viral infections, what other type of infection is in the differential diagnosis for herpetic whitlow?

Streptococcal infection Signup and view all the answers

What is a common patient population that may experience severe or chronic HSV infections?

Immunocompromised patients Signup and view all the answers

What is one clue that helps make a diagnosis for herpetic whitlow?

Recurrences in the same location Signup and view all the answers

What type of ablative procedure can lead to the development of HSV?

Laser procedures Signup and view all the answers

What is the main concern regarding acyclovir resistance in HSV?

It is an increasing concern, particularly for immunocompromised individuals. Signup and view all the answers

Besides foscarnet, what other antiviral agent has shown efficacy in treating acyclovir-resistant HSV?

Cidofovir. Signup and view all the answers

What are the primary limitations of using foscarnet or systemic cidofovir?

Severe renal toxicity and the requirement for intravenous administration. Signup and view all the answers

According to the CDC, what is an alternative topical treatment for acyclovir-resistant HSV, even though it is not FDA-approved?

Compounded topical cidofovir. Signup and view all the answers

What is a major challenge in preventing genital herpes transmission, even with the use of condoms?

It cannot provide absolute prevention of genital herpes. Signup and view all the answers

What is the main approach to prevent genital herpes transmission, besides antiviral therapy?

Patient education regarding prevention of genital herpes transmission. Signup and view all the answers

What type of vaccine is GEN-003, being studied for HSV-2 infection?

A therapeutic vaccine. Signup and view all the answers

What was found about the helicase-primase inhibitor pritelivir in randomized controlled studies?

It significantly decreased HSV shedding and fewer days with genital lesions. Signup and view all the answers

What is the primary use case for oral pritelivir being trialed?

Acyclovir-resistant mucocutaneous HSV infections in immunocompromised hosts. Signup and view all the answers

Besides Acyclovir, what other two medications can be used for genital and orolabial HSV in the context of HIV?

Famciclovir and valacyclovir. Signup and view all the answers

What percentage of HSV transmission is estimated to occur during asymptomatic shedding periods?

Between 70% and 80%. Signup and view all the answers

True or False: Antiretroviral therapy always reduces the risk of HIV-1 transmission when prescribed alongside of antiherpetic suppressive therapy.

False Signup and view all the answers

Prior to the varicella vaccine, what percentage of children in the US contracted varicella by age 10?

90% Signup and view all the answers

What are the two clinical forms, or synonyms, for the Varicella-Zoster Virus (VZV)?

Varicella (chickenpox) and Herpes zoster (shingles). Signup and view all the answers

What is the name of the condition caused by the reactivation of latent varicella zoster virus (VZV)?

Herpes zoster Signup and view all the answers

Approximately what percentage of healthy adults experience herpes zoster at some point in their lives?

20% Signup and view all the answers

What percentage of immunocompromised individuals may develop herpes zoster?

50% Signup and view all the answers

In what year was the link between varicella and herpes zoster first recognized?

1888 Signup and view all the answers

Who first described the development of varicella in children after exposure to those with herpes zoster?

von Bokay Signup and view all the answers

What discovery confirmed that the etiologies of varicella and herpes zoster were identical?

The identification of the same virus in both diseases. Signup and view all the answers

What is the approximate percentage decrease in the overall incidence of varicella following the introduction of the varicella vaccine in 1995?

85% Signup and view all the answers

What is the most common presentation of chronic HSV in immunocompromised individuals?

Chronic, enlarging ulcerations are the most common presentation. Signup and view all the answers

What is a pathognomonic finding in ocular HSV infections?

Branching dendritic lesions of the cornea are pathognomonic for ocular HSV infections. Signup and view all the answers

What is the most common cause of fatal sporadic viral encephalitis in the United States?

Herpes simplex virus (HSV) is the most common cause of fatal sporadic viral encephalitis in the US. Signup and view all the answers

Which lobe of the brain is often involved in HSV encephalitis?

The temporal lobe is often involved in HSV encephalitis. Signup and view all the answers

What are common symptoms of HSV proctitis?

Common symptoms include diarrhea, anal pain, and a feeling of rectal fullness. Signup and view all the answers

What is the most common mode of transmission for neonatal HSV infections?

Neonatal HSV infections usually result from exposure to HSV during a vaginal delivery. Signup and view all the answers

What is the typical age of onset for neonatal HSV infections?

The typical age of onset is from birth to 2 weeks, but usually ≥5 days of age. Signup and view all the answers

Besides skin lesions what other areas of the body can be affected by neonatal HSV?

Neonatal HSV can also involve the oral mucosa, eye, CNS, and multiple internal organs. Signup and view all the answers

What is the risk of transmission of HSV from mother to baby with a primary infection?

The risk of transmission is 30-50% when a mother has a primary HSV infection near delivery. Signup and view all the answers

What is the risk of mortality due to HSV encephalitis without treatment?

Mortality is ≥70% without treatment. Signup and view all the answers

What is the risk of transmission of HSV from mother to baby with a recurrent infection?

The risk of transmission is low, with ~ 3% if the mother has recurrent infections . Signup and view all the answers

Besides HSV-1, what other HSV type can cause ocular infections?

HSV-2 can cause ocular infections in newborns. Signup and view all the answers

Which medication can increase the risk of HSV and VZV encephalitis and meningitis?

Natalizumab, used to treat multiple sclerosis and Crohn disease, can increase the risk of HSV and VZV encephalitis and meningitis. Signup and view all the answers

What finding is pathognomonic for ocular herpes?

Branching dendritic lesions of the cornea are pathognomonic. Signup and view all the answers

What underlying factor increases the risk of developing herpes lesions?

Immunocompromised states such as in solid organ transplant patients, individuals with HIV, or leukemia/lymphoma. Signup and view all the answers

Study Notes

Human Herpesviruses

Human herpesviruses (HHVs) are categorized into three groups: alpha, beta, and gamma herpesvirinae.
Each virus has a core of linear double-stranded DNA, an icosahedral capsid (100-110nm in diameter), and an envelope with glycoprotein spikes.
Pathogenesis of herpesvirus infections follows primary infection, latency, and reactivation.

Herpes Simplex Viruses (HSV-1 and HSV-2)

HSV-1 and HSV-2 are ubiquitous pathogens that primarily cause orolabial and genital infections.
Genital herpes is one of the most common sexually transmitted infections worldwide.
Epidemiology of HSV infections can be deciphered using sensitive and specific serologic markers.
Antiviral therapy controls the course of HSV disease.
HSV-1 is more frequently associated with orolabial infections, while HSV-2 is more frequently associated with genital infections.
Primary, non-primary initial, and recurrent infections can each be symptomatic or asymptomatic. Approximately one-third of the world's population has experienced a symptomatic HSV infection.

Epidemiology

HSV-1 infections are more common among children under 10.
HSV-1 antibodies are present in 50-90% of people aged 20-40 globally.
HSV-2 is the leading cause of recurrent genital herpes infections worldwide (70-90%).
HSV-1 is the leading cause of genital herpes in young adults in the US, Canada and UK.
Factors associated with acquisition of genital herpes include age 15-30, increased number of sexual partners, lower income and education levels. HIV-positivity increases risk of acquiring and transmitting HIV.

Pathogenesis

HSV transmission can occur during asymptomatic periods of viral shedding.
HSV-1 is mainly transmitted through saliva contact.
HSV-2 is mainly transmitted through sexual contact.
Virus replicates at the mucocutaneous site of infection, then travels to the dorsal root ganglia where it establishes latency.
Latency allows the virus to exist in a non-infectious state.
HSV-1 can induce intracellular accumulation of CD1d molecules.
HSV evades detection and establishes latency by down-regulating various immunologic cells and cytokines.

Clinical Features

HSV infections can have a wide range of clinical presentations.
Asymptomatic infection is very common.
Primary infections typically appear 3-7 days after exposure.
A prodrome of tender lymphadenopathy, malaise, anorexia, and fever typically precedes the onset of mucocutaneous lesions.
Painful, grouped vesicles appear on an erythematous base, becoming pustules, erosions, or ulcerations with a characteristic scalloped border. Lesions typically resolve in 2-6 weeks.
Recurrent lesions are generally less severe and fewer in number compared to primary infections.
Primary orolabial infections are often asymptomatic and present as gingivostomatitis in children, or pharyngitis in young adults.
Common localization for HSV-1 is on the lips, buccal mucosa, gingivae (Fig. 80.1A,B).
Recurrent herpes labialis (cold sores/fever blisters) frequently appear on the lip's vermilion border (Fig. 80.1C).
Genital herpes infections are frequently asymptomatic, though painful erosive balanitis or vulvovaginitis are possible.
These lesions can impact the cervix, buttocks, and perineum in women.
Systemic complaints and complications are more common in women.
HSV infections often involve the skin and mucous membranes.

Diagnosis and Pathology

HSV diagnosis uses viral culture, DFA assays, molecular techniques, and serology.
Polymerase chain reaction (PCR) is a rapid, sensitive, and specific method for detecting HSV DNA.
A Tzanck smear of early lesions can reveal multinucleated giant cells.

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Description

Test your knowledge on herpesvirus infections, including stages of pathogenesis, genetic material, and common manifestations. This quiz covers topics such as HSV infections, skin barrier impairment, and differential diagnoses. Ideal for students studying virology or infectious diseases.