VZVrelated

VZV-related refers to diseases and topics connected with Varicella Zoster Virus (VZV), a human alphaherpesvirus. VZV causes two principal clinical entities: varicella (chickenpox) during primary infection and herpes zoster (shingles) upon reactivation later in life. After primary infection, the virus becomes latent in dorsal root and cranial nerve ganglia and can reactivate years later, often under conditions of aging or immunosuppression. Transmission occurs mainly through respiratory droplets or contact with vesicular fluid.

Virology and pathogenesis: VZV is a double-stranded DNA virus that establishes lifelong latency in sensory ganglia. During reactivation, viral replication leads to a painful, vesicular rash in a dermatomal distribution. In some cases, dissemination can occur, particularly in immunocompromised individuals, potentially affecting multiple organ systems. Ophthalmic involvement in zoster can threaten vision and requires prompt attention.

Clinical spectrum: Varicella typically presents with a generalized itchy vesicular rash, fever, and malaise, most common in children but also seen in adults. Shingles presents as a unilateral, dermatomal vesicular eruption with significant acute pain; postherpetic neuralgia can follow. Varicella can be more severe in adults, pregnant individuals, newborns, and those without prior immunity.

Diagnosis and treatment: Diagnosis is usually clinical, supported by PCR testing of lesion fluid or vesicular fluid in unclear cases. Antiviral therapy with agents such as acyclovir, valacyclovir, or famciclovir is most effective when started early. Pain control and careful monitoring are important, especially for high-risk groups. Vaccination is a key preventive measure: varicella vaccine for children and susceptible adults; the recombinant zoster vaccine (Shingrix) for adults, typically starting at age 50, with boosters as recommended.

Public health and research: Vaccination programs have reduced incidence and complications. Ongoing research investigates vaccine effectiveness, antiviral resistance, and strategies to prevent postherpetic neuralgia and severe VZV disease in high-risk populations.