Varicella Zoster Virus (VZV) Infection in Children

Etiological Agent

The Varicella virus, a double-stranded DNA virus that is a member of the Herpesvirus family, is the cause.

Mode Of Infection

The Droplet Route, respiratory infections, and closed contact account for the majority of cases.

Incubation Period

The incubation time spans between 10 and 21 days. Generally, if a median value is taken, 14–16 days.

Period of Infectivity

Up until all lesions have crusted, the maximum time of infectivity is 24-48 hours prior to the rash.

Problem of Latent Infection in VZV

 A latent infection may manifest as a clinical illness or during the incubation phase.  The virus travels backward through the spinal cord and cranial nerve ganglia, passing through sensory axons to the dorsal root ganglia. Latent infections could potentially be influenced by viremia.  Later on, Herpes Zoster may result from a recurrent infection.

Clinical Features of VZV

The first signs, known as prodromal symptoms, include moderate fever, headache, and anorexia after an incubation period of 10–21 days.  A rash appears 24–48 hours later and develops normally from there.
  At first, there is a macule. It becomes papules after a few days, develops into a clear fluid-filled lesion known as vesicles with surrounding erythema, and finally resolves by crusting.

Rash Possesses a Few Traits.

A pruritic rash is another name for an irritating rash. Centripetal rash, which starts in the trunk and then moves to the face and limbs.
Crops frequently sustain injuries, various lesions with various morphologies may be present in the same patient. For every crop, the rash normally disappears in 3–7 days by crusting. Compared to youngsters, adults are more likely to sustain scars.

Complications of Varicella Zoster Virus (VZV)

• Secondary bacterial infections, primarily caused by gram-positive bacteria such as Staphylococcus aureus and Streptococcus pyogenes, are the most frequent consequence of chickenpox.
• Complications involving the Central Nervous System (CNS) are particularly frequent; meningoencephalitis and acute cerebellar ataxia being the most common among them.
• Purpura fulminans, a condition where antibodies against Protein C cause huge purpuric bullae to appear all over the body, can occur.
• In these kids, stroke and Reye's syndrome can happen infrequently.
• The more often in adults than in children, herpes zoster can induce latent infection and reactivation.
• It causes a Dermatomal Rash, which is characterized as a searing agony that usually leaves scars behind. Thankfully, it appears with herpes zoster.

Also Read: Pediatric Viral Infection With Rash- Measles

Treatment

Acyclovir is the recommended medication for treating chickenpox. The recommended dosage is 20 mg/kg/dose, taken orally four times a day for a maximum of five days. The medication should ideally be begun within 24 hours of the rash starting.

The American Academy of Pediatrics (AAP) does not regularly suggest acyclovir medication for treating uncomplicated varicella in otherwise healthy children. • Intravenous therapy is indicated for severe illness and varicella in immunocompromised patients.

In HIV, acyclovir-resistant V2V might be observed. They require intravenous foscarnet there.  In the event that resistance to foscarnet arises, they proceed with a Cidofovir trial.

Progressive varicella is associated with immunocompromised patients, pregnant women, and occasionally healthy individuals.  Aspirin is contraindicated in cases of chickenpox because of the risk of Reye's syndrome.  Ibuprofen is contraindicated because of the risk of necrotising fasciitis.

Extensive recurrent crops of new lesions are linked to progressive varicella. Furthermore, there is the beginning of significant systemic involvement that results in myocarditis, encephalitis, and other related consequences, all of which typically have a high fatality rate.

Hope you found this blog helpful for your NEET SS Pediatrics Infections preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs.