The Native Antigen Company is part of LGC Clinical Diagnostics - Learn More

0 Items
Select Page

Varicella-Zoster Virus

Varicella zoster virus (VZV, also known as human herpesvirus 3) is a ubiquitous alphaherpesvirus with a double-stranded DNA genome. VZV only infects humans, with no animal reservoir and causes chickenpox (varicella), a disease most commonly affecting children, teens, and young adults. Varicella is usually a self-limiting disease, but adults, infants and individuals who are severely immunocompromised are at higher risk of severe complications and death. Following infection, the virus remains latent in nerve cells and may be reactivated causing a secondary infection (herpes zoster), commonly referred to as shingles.

Varicella-Zoster Virus ​ Background

Varicella-zoster virus (VZV or human alphaherpesvirus 3 [HHV-3]) is a very common virus which is highly contagious. It is an enveloped double-stranded DNA virus and one of nine herpesviruses known to infect humans. Phylogenetic analysis of VZV genomic sequences resolves wild-type strains into nine genotypes (E1, E2, J, M1, M2, M3, M4, VIII and IX). There are at least five clades of VZV. Clades 1 and 3 include European/North American strains; clade 2 are Asian strains, particularly Japan; and clade 5 is apparently in India. Clade 4 includes some strains from Europe but its geographic origins are not yet clarified.

Varicella occurs worldwide and is endemic in populations of sufficient size to sustain year-round transmission, with epidemics occurring every 2–3 years. It shows a strong seasonal pattern, with peak incidence during winter and spring or during the cool, dry season. VZV infections are species-specific to humans, but it can survive in external environments for a few hours (Gershon et al., 2015). The epidemiology of the disease differs between temperate and tropical climates. The reasons for the differences are poorly understood and may relate to properties of VZV (known to be sensitive to heat), climate, population density and risk of exposure (e.g., attendance at childcare facility or school or the number of siblings in the household) (WHO).

The virus is highly communicable and spreads by the airborne route, with an extremely high transmission rate in temperate countries. Most virus comes from skin where it is highly concentrated in vesicles; indeed, skin cells and cell-free VZV are frequently shed and are probably the major source of infectious cell-free airborne virus. Infected children without skin lesions are not contagious to others (Gabutti et al., 2016).

VZV causes two human diseases, varicella (chickenpox) and herpes zoster (shingles). Chickenpox (varicella), is a disease most commonly affecting children, teens, and young adults, and shingles (herpes zoster) in adults; shingles is rare in children. VZV multiplies in the lungs, and causes a wide variety of symptoms. Varicella is generally self-limited and vesicles gradually develop crusts, which disappear over a period of 7-10 days. Individuals remain contagious until all lesions have crusted over. The disease is typically mild, but severe complications may arise, including bacterial infections (e.g. cellulitis, pneumonia) and neurological complications (e.g. encephalitis), and these can be fatal. Disease is associated with higher morbidity and mortality in infants and in individuals with an impaired immune system (WHO). Herpes zoster is a reactivation of a latent VZV infection. After the primary infection (chickenpox), the virus lies dormant in the nerves, including the cranial nerve ganglia, dorsal root ganglia, and autonomic ganglia. Many years after the person has recovered from chickenpox, VZV can reactivate to cause neurological conditions. Antiviral drugs and vaccines against both varicella and zoster are available and are effective in treating and preventing VZV-induced disease (Gabutti et al., 2016). Multiple vaccine formulations of the live attenuated vaccine, based on the Oka VZV strain, have been available since 1974 and Varicella vaccines are available as a single antigen and in combination with measles, mumps and rubella vaccine.

References

  • Gabutti G, Franchi M, Maniscalco L, Stefanati A. Varicella-zoster virus: pathogenesis, incidence patterns and vaccination programs. Minerva Pediatr. 2016 Jun;68(3):213-25.
  • Gershon AA, Breuer J, Cohen JI, Cohrs RJ, Gershon MD, Gilden D, Grose C, Hambleton S, Kennedy PG, Oxman MN, Seward JF, Yamanishi K. Varicella zoster virus infection. Nat Rev Dis Primers. 2015 Jul 2;1:15016.
  • WHO. Immunization, Vaccines and Biologicals. Varicella.

Varicella-Zoster Virus

We are pleased to offer a highly purified recombinant Varicella-Zoster virus antigens, manufactured in mammalian cells using bespoke expression and purification methods.

 

Questions?

Check out our FAQ section for answers to the most frequently asked questions about our website and company.

Hendra and Nipah Viruses: Catalysing Urgency in Vaccine Development and Diagnostic Advancements

Hendra and Nipah viruses are two closely related pathogens that belong to the genus Henipavirus within the family Paramyxoviridae. These viruses have garnered significant attention due to their zoonotic nature and their potential to cause severe and often fatal...

Monkeypox; 3 months on

It has been 3 months since a new, unusually widespread outbreak of Monkeypox was first identified. What was normally a virus confined to limited infections in the West African continent is becoming a global health concern.   What have we learned about this virus...

COVID-19 Underlines the Need for Universal Vaccines

This article was originally published on Clinical Lab Manager. In recent history, humanity has witnessed numerous emerging viral diseases, including the SARS, MERS, and SARS-2 coronaviruses, as well as HIV, Zika, Ebola, and H1N1 and H3N2 influenza. None have tested...

Tick-Borne Diseases: The Need for Integrated Approaches to Human-Animal Diagnosis

This article has been published in Volume 8, Issue 3 of International Animal Health Journal. Ticks are responsible for a diverse group of neglected, and rapidly expanding diseases, affecting humans, companion animals and livestock. A growing understanding of tick-host...

The Continued Challenges of Flavivirus Serology

This article was originally published on the Science Advisory Board. Flaviviruses are a genus of positive-sense RNA viruses, largely transmitted by mosquito and tick vectors that cause infections, including yellow fever, dengue, the Zika virus, West Nile virus,...

Get in Touch

We sometimes send exclusive information and offers to our customers - please let us know if you are happy to receive these

6 + 6 =