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 zoster 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...
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...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.
[1, 4, 5, 9, 13] There have been no documented cases where a human has contracted the disease from another human. [4] It appears, based on field and lab data, that infection requires direct contact with the virus through means such as contact with infective bodily secretions, urine, or tissues. [12] It is unknown to scientists how the virus can be maintained in the bat populations and avoids extinction as the host species becomes immune to its presence. [14] The incubation period from time of infection to the onset of symptoms is about 5-14 days in experimentally induced animals [4] and 8-14 days in natural field cases.
Shingles, herpes zoster, is a very contagious and painful rash, or blister that appears on the skin. These rashes most commonly appear on the sides of the body in stripes. The stripes are made up of many very painful blisters caused by a certain type of virus. The varicella zoster, most commonly known as the chicken pox virus attacks the nerve roots in that area. The herpes zoster virus is in the herpes family, including HSV, herpes simple virus, which causes cold sores, fever blisters, and genital herpes. (WebMD, 2011) Most people are required to get the chicken pox shot when they are children although some do not. The chicken pox shot helps to keep out the virus by keeping it dormant in the nerves. The varicella zoster virus stays in a few cells; this is how shingles appear suddenly. It appears when the dormant cells become active in the later years of life.
Cytomegalovirus (CMV) is the most common virus in the United States that can infect almost any individual. Cytomegalovirus is also referred to as Herpesvirus-5, which belongs to a branch of Herpesviridae family. Herpesviridae has a spherical shape that contains four significant elements that are important to the viron. The four elements are the core, tegument, capsid and the envelope. Alphaherpesvirinae, Betaherpesvirinae and Gammaherpesvirinae are three subfamilies which belong to Herpesviridae. Cytomegalovirus belongs to the Betaherpesvirinae family, which also include Muromegalovirus and Roseolovirus. The Alphaherpesvirinae subfamily includes Simplexvirus, Varicellovirus, Mardivirus and Iltovirus genera. The Gammaherpesvirinae subfamily contains Lymphocryptovirus and Rhadinovirus genera. The diameter size of the virus is based on each specific family; however, the core remains the same throughout the species, which contains single layer of double stranded DNA tightly condensed in the capsid. In the tegument component, there are 30 or more viral proteins that are shapeless that encompass the capsid. Out of the four major components, the tegument has the most poorly defined structure. On the other hand, the capsid is a well-defined structure that is an icosahedron, which is composed of 162 capsomeres, 12 of which are pentons and 150 are hexons (1). Last but not least, the liquid envelope surrounds the tegument with approximately 10 glycoprotein and cellular proteins. Each subfamily under the herpesviriade has its own arrangement between the liquid envelop and the tegument layer.
The Herpes virus is actually from a family of viruses that include 8 different virus strains that affect humans. The viruses are known through numbers 1 through 8 or HHV1-HHV8. HHV 1 and 2 are listed above while HHV 3, known as varicella zoster virus, and that causes chickenpox. HHV 3 can also cause a recurring skin infection known as herpes zoster or shingles. HHV 4 is known as the Epstein Barr virus, and is responsible for the easily spread mononucleosis, commonly referred to as “mono”. HHV 5 is known as...
HSV-1 is spread through saliva and direct contact, such as kissing, sharing eating utensils, sharing drinks or sharing personal items. Children often contract the virus from kissing their parents and coming in contact with other children. HSV-2 is spread through sexual intercourse. HSV must be transported through bodily fluids (saliva, pus, semen, vaginal fluid) to infect cells.3 The virus is transmitted through the mucosal linings of the body or through an open wound and has an incubation period of 2-12 days.4
Chicken pox, or Varicella-Zoster, lies dormant in a person’s cerebral ganglia or in the ganglia of the posterior nerve roots after the person has an outbreak. Typically the virus will remain dormant for the rest of the person’s life, without a reoccurrence. Although there are instances when the virus will “awaken” or become active again,...
Mumps is a paramyxovirus that is closely related to the parainfluenza virus. Its symptoms were first described in the 5th century BC, and it was a very common childhood affliction until the last several decades. It was identified as a virus in 1934, and an effective vaccine was developed in 1967. Mumps is acquired by aerosol, necessitating close human interaction for spread. Human beings are the only known reservoir for mumps virus, and there is only one serotype.
been previously touched by an infected person, will transmit the disease to the healthy person who
Hepatitis B virus (HBV) is a severe and common virus that has infected ‘more than two billion people alive today at some point in their life.’1 It is a hepadanavirus that interferes with the liver functions as it replicates in the hepatocytes (liver cells) and induces a immune response that is responsible for the inflammation of liver.2 Viruses are not motile, which means that HBV is also sessile and does not form spores. The spherical virion, is called a Dane Particle3 that is 42nm in diameter binds to the surface of hepatocyte.1 The virion itself contains an inner protein core, 27nm thick filled with circular partially double stranded DNA, DNA polymerase and reverse transcriptase.1 It is an enveloped virus, so it also holds an outer lipoprotein envelope4 that is 7nm thick and is comprised of many embedded surface proteins such as surface antigen for viral binding and entry.1 HBV has an average incubation period of three months, which means that it does not start showing symptoms for the first three months that the person is infected and that person can unknowingly infect others.2 ...
...or children. The specific way of transmission is difficult to identify. Most common assumptions have been that transmission has occurred through skin lesions or by sharing blood contaminated objects. Infected saliva is another source of infection especially as a non-parental infection. The virus has the ability to enter a healthy body as an airborne disease by coughing and sneezing, from mouth-to-mouth kissing, biting or by sharing chewed toys and candies [2, airborn]
In 1992, there was approximately 158,000 people reported to have Chickenpox across the world (National Vaccine Information Center, 2017). As a result, there are 100 deaths that are publicly known (National Vaccine Information Center, 2017). These deaths consisted of mainly adults (National Vaccine Information Center, 2017). Chickenpox is more serious in adults than in children (National Vaccine Information Center, 2017). Adults, infected with the Chickenpox virus, have a 20 percent chance of developing severe complications, such as pneumonia (National Vaccine Information Center, 2017). Other Chickenpox complications that may occur are lesions, bacterial infections, and brain inflammation (National Vaccine Information Center,
Viruses can be transmitted in many ways. Being in contact with an infected person will most likely transfer the virus. One can also obtain the virus through swallowing, inhaling, and unsafe sex. Poor hygiene and eating habits usually increase the risk of catching a viral infection. Contracting a viral infection is followed by adverse s...
Chicken pox is not an Entrée that is served at one’s family holiday dinner party. Chicken pox is an extremely contagious disease caused by the Varicella zoster virus. Chicken Pox is not a disease that is known to affect other animals or insects. Unlike other diseases, where human and other animal close interaction causes the exchange of virus and disease this disease did not come from a human-chicken interaction. The name chicken pox has been stuck for generations; there are many theories behind its name. Chicken pox could sneak up on its young victims in the form of an innocent touch, or by inhaling tiny particles from a cough, or sneeze which then enters the respiratory tract. Once the virus attaches itself to it gracious, and unwilling host cells it causes a crimson rash that could be located on different parts of the body. The rash is highly irritating which makes it almost impossible not scratch. In the United States each year about 5,000 to 9,000 people are hospitalized, and around 100 people die from the microbe Varicella zoster that causes chicken pox.
Recent research shows that, there are three major means by which infections can be transmitted and they include direct transmission, indirect transmission and airborne transmission (Hinman,Wasserheit and Kamb,1995). Direct transmission occurs when the physical contact between an infected person and s susceptible person takes place (division of public health, 2011). An example is a health care worker who attends to an Ebola patient, without gloves, gown and mask plus forget to wash his or her hand with soap and hot water and or a person having flu without the use of mask or washes his hand after sneezing easily passes the infection to the other through hand shake or surface touch, living the bacteria there for another vulnerable person to also touch if the surface is not disinfected with bleach. Studies makes it clear that, the spreads takes effect when disease-causing microorganisms pass from the infected person to the healthy person through direct physical contact such as touching of blood, body fluids, contact with oral secretion, bites kissing, contact with body lesions and even sexual contact. However, measles and chicken pox are said to be conditions spread by direct
It is noticed that science develops in splashes, each significantly advancing our understanding of the nature. The 19th century was the time of rapid development of microbiology. In the search for secrets of nature science has reached extremely high and low energies as well as large and small length scales. Still until recently we knew very little about one of the most complex aspects of life – microbes and infection. Now we are at the dawn of efflorescence in molecular biology, which provides an excellent basis for application into several areas of biology like cancer and virology . Revelations of molecular biology become extremely crucial, as they provide insights into the way molecules work.