Varicella-zoster virus, or VZV, is known as the chicken pox and related to shingles. This virus is made up of four basic morphology elements: envelope, tegument, capsid and core. The outer layer of the virus is the nuclear membrane. Under this is the tegument. Tegument is very thick. Its dense properties are located around the cytoplasmic vacuoles. This area has receptors that encode protein. Protein is vital for viruses and is the basic offence used to survive and mutate. At the center of this virus is the necleocapsid which is also made up of proteins. This element of varicella-zoster is found in all viruses of the herpesvirdae family. Scientists are unable to distinguish the necleocapsid from others found in this family. For that reason, VZV is related to the herpes. This includes chicken pox (varicella-zoster) and shingles (herpes zoster). Varicella-zoster and others of the herpesvirdae family have a DNA genome. VZV is 180-200nm in diameter and has a round, spherical shape, (Gross & Doerr, 2006).
Chicken pox and shingles have different characteristics. This includes the difference in dormancy and contaminants. Ironically, they are one part of a family of viruses. This family is called VZV. Varicella-zoster is the virus that causes chicken pox. Herpes zoster is the virus that causes shingles. People who receive the chicken pox have a 10% to 20% chance they will have shingles. There is also a vaccination for shingles. This is available to people over the age of 60, (Chickenn Pox, 2012). To receive this vaccine the adult must have no history of varicella-zosters.
VZV is also associated with other viruses in the herpes family. VZV has a total of 8 variations. The herpes family includes cold sores (HSV-1), genital herpes (HSV-2), mononucleosis (CMV), and Epstein-Carre (EBV) another form of mononucleosis. In 1995 a vaccine was approved by the FDA that reduces the rate of VZV in children. Chicken pox was first thought to be related to small pox. However, in the 18th century it was better defined and removed from the small pox family, (Barton, 2011).
VZV effects human physiology by using its core, the DNA protein structure. It will transfer DNA from its capsid in a human cell. VZV changes shape during this transfer and starts to send messages to the host cell. The message is sent in a sequence of codes repeated until the cell is taken and replicated. VZV can only habitat in primates. The human body is unable to fight against VZV when it enters through the respiratory system. In the respiratory system the virus enters the lymphoid system and incubates there. (Wong, 2006). VZV comes in different forms, chicken pox and shingles. Chicken pox and shingles affect the skin. It is able to reach the skin through the lymphoid system and blood stream. Herpes zoster is also called shingles. Herpes zoster reacts different than varicella-zoster. This form of herpes finds nerve cells in the body to sit and wait. They are attracted to nerve cells dorsal root ganglia, (Chicken Pox, 2011). Herpes-zoster will wait and lay dormant until the immune system is weakened.
Varicella-zoster will incubate in the human body for a period of time. This is between 10 to 20 days before the body will show symptoms. The first symptoms are minor. This includes swelling, headache, and fever. After this there is a rash. The rash is a bump. This small bump is red and raised above the surface of the skin, spreading quickly. In hours the bumps become blistered. The blister will ooze fluid. At first the liquid is clear and then become cloudy, (Chicken Pox, 2011). After this the blister will dry and scab over. This irritates the skin making it itch. Each Individual is different so people will have more bumps than others. This lasts until all the blisters are scabbed over. The process takes between 4 to 7 days, (Chicken Pox, 2011).
Herpes-zoster is an isolated rash and appears on one area of the body. Herpes-zoster has more than one symptom. These happen in different stages. Prodromal is called the first stage. This stage is associated with pain. The area where the rash will appear becomes painful, numb, sensitive, and itchy, (Chicken Pox, 2011). This will last between 1-5 days. Active shingles is the second stage. During this stage there is still pain on the affected area when the rash surfaces. Red bumps develop and blister. The blisters grow and fill with crust. It takes a long time for blisters to heal, lasting months in people with weak immune systems. The last stage is called Post Herpetic Neuralgia, (Chickin Pox, 2011). This stage is also painful. However, not everyone experience the last stage.
Varicella-zoster, V ZV is spread through contact. The contact does not have to be direct or person to person. This virus can be received by airborne pathogens or through droplets. People expel droplets when coughing or sneezing. It can also be received by exchanging saliva. In addition, VZV can be transferred through contact with infected items. This includes items such as clothes and paper. Lastly, a receiver can become infected by contact with an open blister. People who receive VZV can only transfer the virus in a short time. It can happen three days before the onset of symptoms. The receiver is no longer contagious when the blisters of VZV scab over, (Chicken Pox, 2011).
Before vaccination, 95% of the population was infected by the chickenpox at least once in their lifetime. Today, only 10% of people under the age of 15 have experienced the varicella-zoster, (Bilich, 2012). Varicella-zoster heavily affected children between the ages of 5 and 10. Adults and babies can also become infected with, but this can be harmful for these individual. However, harmful cases occur more often in males than females, (Chicken Pox, 2011). Herpes-zoster, on the other hand, affects older adults. This is most often seen in adults over the age of 50.
People at risk of getting the virus are those who never had varicella-zoster or the varicella virus vaccine. Those with weakened immune systems are also at risk of VZV. VZV can cause death. Half the people who become infected with the virus as an adult expire as a result. Varicella can cause death in adults by complicating the central nervous system, (Chicken Pox, 2012). Receiving herpes-zoster can also increase risks for adults who experience this virus. People over 60, have weakened immune systems, under stress, or receive cancer treatment are also at increased risk, (Chicken Pox, 2012). Adults with herpes zoster can also catch a bacterial infection from a blister. When herpes zoster appears on the face if can impair vision if near the eye. It can also be harmful if it enters the nose. If the virus affects the ears or parts of the face, it can make the nerves of the face to become weak. This will cause numbness, weakness, and deafness. Fatalities in children are as much as 20%. Children infected with VZV under the age of 4 were likely to have severe symptoms. Varicella-zoster can create a bacterial infection in a blister. It can also encourage the onset of asthma and pneumonia.
To treat varicella-zosters children should never take aspirin to relieve symptoms. Aspirin can encourage, Rey Syndrome. Reye syndrome is a disease that causes brain damage and endangers the liver. Baths can relieve itching with oatmeal or oatmeal powder, lotion, Benadryl, and mittens to prevent scratching. Adults with varicella-zosters should use the antiviral drug, acyclovir, (Chicken Pox, 2012). This can reduce onset of pneumonia.
Shingles treatment includes pain management. Acyclovir can also be used to treat herpes zoster. Oral corticosteroids also help. Clothing should be loose and away from the skin. Cold therapy should be applied to blisters. Blisters should be allowed to burst on its own and covered, away from airborne pathogens with loose cloth. Danger zones should be monitored. This includes the ears, nose, mouth, and forehead. Herpes zoster in or near these areas can have disastrous effects.
Many people fully recover from varicella virus. Yet, some people do not. Often scaring and scabbing occurs. Blisters that are scratched vigorously can create permanent scars. Varicella-zoster can encourage ear infections in children and result in hearing loss. Adults with varicella-zosters are at high risk of pneumonia that can delay treatment and recovery. Varicella pneumonia can encourage lung scarring as well. The risks to adults are high. Adults with varicella-zoster can also result in strong, encephalitis and meningitis. Varicella virus vaccination has decreased cases of chicken pox by 90%, (Chicken Pox, 2012).
It can take a while for adults to fully recover from shingles. Some never fully recover. People who get PHN or post herpetic neuralgia experience long periods of pain. This can last as long as three months, (Chicken Pox, 2012). Herpes zoster can cause scaring, hear loss, and vision lost. Others may also loose taste. Belles Palsy can also occur, causing face paralysis.
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