Sandbox: Dr.Reddy

• VZV can be spread by varicella or herpes zoster carrying:
  • Patients
  • Health care providers
  • Visitors
• Individuals susceptible to the be infected by VZV include:
  • Patients and health care providers in hospitals
  • Long-term-care facilities
  • Other healthcare settings
• These transmissions have been attributed to
  • Delays in the diagnosis of varicella and zoster
  • Delay in the reporting of varicella and zoster
  • Failures to promptly implement control measures

Immunocompromised Patients

• Immunocompromised persons who get varicella are at risk of developing visceral dissemination (VZV infection of internal organs) leading to pneumonia, hepatitis, encephalitis, and disseminated intravascular coagulopathy. They can have an atypical varicella rash with more lesions, and they can be sick longer than immunocompetent persons who get varicella. The lesions may continue to erupt for as long as 10 days, may appear on the palms and soles, and may be hemorrhagic.

People with HIV or AIDS

• Children with HIV infection tend to have atypical rash with new crops of lesions presenting for weeks or months. HIV-infected children may develop chronic infection in which new lesions appear for more than one month. The lesions may initially be typical maculopapular vesicular lesions but can later develop into non-healing ulcers that become necrotic, crusted, and hyperkeratotic. This is more likely to occur in HIV-infected children with low CD4 counts.

• In adults, the disease can be more severe, though the incidence is much less common. Infection in adults is associated with greater morbidity and mortality due to pneumonia, hepatitis and encephalitis. In particular, up to 10% of pregnant women with chickenpox develop pneumonia, the severity of which increases with onset later in gestation. In England and Wales, 75% of deaths due to chickenpox are in adults. Inflammation of the brain, or encephalitis, can occur in immunocompromised individuals, although the risk is higher with herpes zoster.Necrotizing fasciitis

• Secondary bacterial infection of skin lesions, manifesting as impetigo, cellulitis, and erysipelas, is the most common complication in healthy children. Disseminated primary varicella infection, usually seen in the immunocompromised or adult populations, may have high morbidity. Ninety percent of cases of varicella pneumonia occur in the adult population. Rarer complications of disseminated chickenpox also include myocarditis, hepatitis, and glomerulonephritis.

Primary varicella (chickenpox)

• Primary varicella is a common childhood disease in Western countries, which presents as pruritic macules, papules, vesicles, pustules, and crusts, usually on the back, chest, face, and abdomen.
• In immunocompetent children, chickenpox is generally a mild disease with little morbidity and rare mortality.
• Primary varicella is associated with more morbidity in adults. Following resolution of primary varicella, VZV persists in a latent form in dorsal ganglion cells for what is usually an extended period of time. For reasons that are still poorly understood, VZV can later start replicating in the ganglion, producing severe neuralgia and spread of the virus down the sensory nerve. Vesicles then appear on the skin in the distribution of this nerve, producing the characteristic dermatomal rash of shingles. The vesicles progress to pustules, then to crusts that eventually are lost. Scarring and changes in pigmentation can result, but the most frequent sequela of zoster is postherpetic neuralgia, which is usually most severe in the elderly.
• In immunocompromised patients can sometimes involve internal organs (eg, lungs, liver, brain) resulting in high rates of morbidity and mortality.
• Primary varicella or herpes zoster Congenital VZV infection is uncommon but can result in severe congenital malformations.
• A Tzanck smear can be useful to demonstrate a herpesvirus infection, but confirmation of VZV as the cause of the infection requires at least one of the following tests: culture, serology, direct immunofluorescence staining, or molecular techniques.

Zoster (shingles)

• Anyone who has recovered from chickenpox may develop shingles; even children can get shingles. The risk of shingles increases as one gets older. About 50% all cases occur in men and women 60 years old or older. One in every three people develop shingles in their lifetime which is estimated at 1 million cases every year.

• Certain cancers like leukemia and lymphoma, human immunodeficiency virus (HIV) positive individuals, and people on immunosuppressive drugs such as steroids and drugs given after organ transplantation have a greater risk of getting shingles.

• Shingles typically occurs only once in a person's lifetime. However, a person can have a second or even a third episode.

• Some studies have found that VZV dissemination to the visceral organs is less common in children with HIV than in other immunocompromised patients with VZV infection. The rate of complications may also be lower in HIV-infected children on antiretroviral therapy or HIV-infected persons with higher CD4 counts at the time of varicella infection. Retinitis can occur among HIV-infected children and adolescents.

• Most adults, including those who are HIV-positive have already had varicella disease and are VZV seropositive. As a result, varicella is relatively uncommon among HIV-infected adults.

Neonates

• Varicella infection in pregnant women can lead to viral transmission via the placenta and infection of the fetus. If infection occurs during the first 28 weeks of gestation, this can lead to fetal varicella syndrome (also known as congenital varicella syndrome). Effects on the fetus can range in severity from underdeveloped toes and fingers to severe anal and bladder malformation. Possible problems include:

• • Damage to brain: encephalitis, microcephaly, hydrocephaly, aplasia of brain
  • Damage to the eye (optic stalk, optic cap, and lens vesicles), microphthalmia, cataracts, chorioretinitis, optic atrophy
  • Other neurological disorder: damage to cervical and lumbosacral spinal cord, motor/sensory deficits, absent deep tendon reflexes, anisocoria/Horner's syndrome
  • Damage to body: hypoplasia of upper/lower extremities, anal and bladder sphincter dysfunction
  • Skin disorders: (cicatricial) skin lesions, hypopigmentation

• Infection late in gestation or immediately post-partum is referred to as neonatal varicella. Maternal infection is associated with premature delivery. The risk of the baby developing the disease is greatest following exposure to infection in the period 7 days prior to delivery and up to 7 days post-partum. The neonate may also be exposed to the virus via infectious siblings or other contacts, but this is of less concern if the mother is immune. Newborns who develop symptoms are at a high risk of pneumonia and other serious complications of the disease.