Varicella â€Zoster Virus Essay -- Health, Diseases, Chickenpox

Varicella –Zoster Virus (VZV) is a ubiquitous, double standard DNA virus that belongs to the herpes virus group. Like other herpes viruses, VZV may persist in the body after primary infection .VZV is a virus exists across the globe having a high prevalence in temperate climates. It also has a high prevalence in seasons of late winter and early spring. The primary infection results in Varicella (chicken pox) whereas recurrent infection causes herpes zoster (shingles). The virus is approximately 150 to 200 nanometer in size, is the smallest of the known viruses causing herpes and lacks genes for several proteins found in HSV, which is the prototype of the alpha herpes viruses, such as glycoprotein D (Mandell et al., 2009). The virus has a high sensitivity to temperature and becomes inactivated at approximately 56-60 degrees Celsius (Arvin, 1996). If it is was exposed to such a high temperature the viral envelope would be disrupted making the virus not infectious. Varicella zoste r virus produces six or more glycoproteins, such as gB (gpII), gC (gpIV), gE (gpI), gH(gpIII), and gL, which are also expressed on the cell membranes during viral replication (Arvin, 1996). The gE protein is produced abundantly in VZV. The gB protein is the target of neutralizing antibodies and may play a role in virus entry. The gH protein appears to have fusion function, facilitating cell –to-cell spread of the virus. The prevention of the spread of VZV is difficult because contagious persons can go 1 – 2 days without signs and symptoms (Arvin, 1996). VZV is transmitted by respiratory droplets or direct contact with rash lesions, and patients are usually contagious from a few days before rash onset until the rash has crusted over. VZV enters the body throu... ...l VZV infection (chickenpox) can contract chickenpox from someone with recurrent infection (shingles). In such cases, transmission occurs during exposure when the rash is in the blister-phase, not through sneezing or coughing. Treatments that are available consist of antiviral therapy such as acyclovir, famciclovir and valacyclovir (Stoppler, 2011). These antivirals help the severity of varicella and herpes zoster. An important vaccine that is available for people over the age of 60 is called Zostavax. Zostavax is available in the market which can reduce the risk of shingles (Stoppler, 2011). It is a live vaccine that boosts the immune system, provides protections against the virus and it complications. It has shown to reduce the risk of shingles by half in older individuals and also reduces the severity and length of disease in those who still develop shingles.