Varicella Zoster Virus (VZV) – 11-09-2023

Syllabus: GS-2/Health; GS-3/Science

In News

  • While doing a surveillance of mpox (monkeypox) cases in India, the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV) has for the first time found the presence of Clade 9 variant of varicella zoster virus (VZV) in India.

About

  • Names: Varicella zoster virus (VZV) is also known as human herpesvirus 3 (HHV-3, HHV3) or Human alphaherpesvirus 3
  • Type: It is one of nine known herpes viruses that can infect humans. (Herpesviridae is a large family of DNA viruses that cause infections and certain diseases in animals, including humans. The members of this family are also known as herpesviruses).
  • Symptoms and Impact:
    • VZV multiplies in the tonsils, and causes a wide variety of symptoms such as vesicular rashes, fever, myalgia, headache, fatigue, loss of appetite, and lymphadenopathy.
    • It causes chickenpox (varicella) commonly affecting children and young adults, and shingles (herpes zoster) in adults but rarely in children.
    • Monkeypox disease symptoms are frequently mistaken for VZV, as their clinical presentations often closely resemble each other.
  • Transmission and life-cycle:
    • It establishes latency after primary infection, a feature unique to most herpes viruses.
    • After primary infection with VZV (chickenpox), the virus lies dormant in neurons, including the cranial nerve ganglia, dorsal root ganglia, and autonomic ganglia.
    • Many years after the person has recovered from initial chickenpox infection, VZV can reactivate to cause shingles.
  • Treatment:
    • For people exposed to varicella or herpes zoster who cannot receive varicella vaccine, varicella-zoster immune globulin can prevent varicella from developing or lessen the severity of the disease.
    • Certain groups at increased risk for moderate to severe varicella be considered for oral acyclovir or valacyclovir treatment.

Source: TH