Varicella-Zoster Virus

• a herpesvirus

• transmitted by respiratory route

• incubation 11-13 days

• cell-mediated immunity vital for clearing disease

• children 5-9 get mild disease

• teenagers and adults get more severe immune reaction and increased risk of pneumonia

• establishes latency in dorsal root and cranial nerve ganglia

• can cause complications in pregnancy

Diseases

• chickenpox - primary infection

• herpes zoster / shingles - recurrence

• Pneumonitis (immunocompromised)

Complications of infections in pregnancy

• maternal pneumonitis, encephalitis, hepatitis
• 1st 12 weeks -  not such a big risk to foetus
• 12-24 weeks - risk
  • scarring,
  • blindness,
  • distortion of limbs,
  • intracranial calcification,
  • microencephaly
• Ramsay Hunt Syndrome

Laboratory diagnosis

• Scrapings from vesicles

  • cytopathological effects (CPE)

  • immunofluorescence

Treatment

• acyclovir
  • within 24-36 hours of onset of shingles can reduce chance of post-herpetic neuralgia

Prophylaxis

• live attenuated vaccine available
• varicella-zoster immunoglobulin (VZIg) may protect immunocompromised or pregnant mothers who may have been exposed

[ Home ] [ Up ]