Epidemiology: Chickenpox
The Varicella-Zoster virus causes a very infectious disease called Chickenpox. Chickenpox is usually acquired through the inhalation of airborne respiratory droplets from an infected host. Chickenpox is primarily acquired during childhood , with more than 90% of all reported cases occurring in children under the age of 10. A person with chickenpox can spread the virus without even showing any signs or symptoms. It is usually most easily transmitted two to three days before a rash appears and keeps that high transmission rate until the blisters have crusted over.
The following paper provides a detailed description of Chickenpox and the determinants of health contributing to the development of the disease. The epidemiologic triangle is used to explain the relationships among an agent, a host and the environment. The paper also addresses the role of the community health nurse in Chickenpox management and discusses the role of one national organization in the fight against the spread of Chickenpox.
Description of Chickenpox Chickenpox is an infection caused by the Varicella-Zoster virus. It is considered contagious and is characterized by a itchy rash and appears like blisters all over the body . It occurs most frequently in children between the ages of five and eight years old and is transmitted so easily that the majority of the population will catch the disease at some point in their childhood. Chickenpox can be transmitted by coming into contact with an effected persons blisters, exposure to shingles, or through inhalation of airborne droplets exhumed by a person infected with the condition. The incubation period is 10 to 21 days, and it is contagious for about 6 to 8 days after the rash appears or until all of the blisters have dried out (Arvin, 1996) On first coming in contact with the virus there are usually no symptoms until the rash breaks out on the person’s skin. At first, these rashes appear as flat red splotches on various locations throughout the affected person’s body. The rash then become raised and resembles small acne pimples. Over time these bumps develop into vesicles which are small blisters and are very delicate and may burst if pressure is applied to them. The vesicles tend to appear in crops within two to six days all over the infected persons body. They often appear on the head and in the mouth, and then spread to the rest of the body, but can at times appear uniformly over the affected areas. They mostly appear numerously over the shoulders, abdominal/trunk area and back. As these vessels break, the sores then become blister like and form a crust. During this stage the infected person will suffer from sever itching as the crust falls away between days 9 and 13 of the outbreak (Woodruff, 2013). The most common complications of chickenpox is secondary bacterial infection of the skin lesions. It occurs in approximately 1% of cases. Other complications can include pneumonia, encephalitis and cerebellar ataxia, thrombocytopenia and hepatitis (Gnann, 20012). Currently no cure is evident for chickenpox, treatment is more for the sign an symptoms incurred during the process such as fever and itching. Outside of normal precautionary procedures meant to comfort the patient, there is one medication that may help stop infections from getting worse and can also help to reduce the chances of an infection reoccurring. Acyclovir, is an antiviral medicine that is given to certain individuals afflicted with chickenpox. Acyclovir may be prescribed to pregnant women adults, if they visit their GP within 24 hours of the rash appearing, newborn babies, and people with a weakened immune system (Feder, 1990). This antiviral medications decrease the duration of symptoms and the likelihood of postherpetic neuralgia, especially when initiated within 2 days of the onset of rash. Acyclovir does not cure chickenpox, but it can help alleviate the symptoms. The medicine normally needs to be taken five times a day for seven days in order to be effective (Feder, 1990).
Demographic Interest
The major data of chickenpox infection rates in the environment was garnered prior to its introduction and development in 1995. Before vaccines were introduced, varicella was endemic in the United States, and virtually all persons acquired varicella at some point before adulthood (cdc.gov, 2006). It is reported that 4 million cases of chickenpox were recorded in the U.S. each year before the vaccine was introduced. Although some states reported cases of varicella to the CDC, it was eliminated from the list of nationally notifiable conditions in 1981. Children under 10 years of age make up between 75 – 90 % of chickenpox cases. In 1995, due to the availability of the vaccine in the U.S., hospitalizations due to chickenpox has declined by nearly 90% (Hambleton, & Gershon, 2005).

Determinants of Health
Varicella peaks in the months of March through May and throughout the regions with mild temperature. Varicella and herpes zoster occur worldwide and are not restricted to any one geographic location. According to the CDC, the varicella infection is more prevalent among adults than children in tropical areas. It is unknown what the reasons are for the difference of age distribution, possibility is that in rural population varicella infection is not common (cdc.gov, 2006). January was regularly the season and its peak for the varicella infection before the nationwide vaccination was implemented. It was a after the nationwide immunizations in 2004, case numbers of varicella or chickenpox remarkably declined. “There is a significant post-vaccination decrease in incidence among preschool children, with the peak incidence being 66 per thousand for 4 and 5 year-old children before the nationwide immunization and 23 per thousand for 6 year-old children in 2008. Varicella-related hospitalizations also significantly decreased in children younger than 6 years after the nationwide immunization was implemented” (Chang, 2011). Since the introduction of the varicella vaccination program, the incidence of varicella in the United States has declined significantly. However, a person who acquires the disease later in their adult life, experiences more severe symptoms of the disease.

Chickenpox Epidemiologic Triangle
The spread of Chickenpox follows the classic epidemiologic triangle. The disease includes an agent, mode of transmission, and hosts. The disease agent is the Varicella-Zoster. The virus infects a persons nerves which causes different symptoms. Once a person gets the infection, the Varicella-Zoster virus goes inactive in the nerves, including the dorsal root, autonomic, and cranial nerve ganglia. Unfortunately, sometimes during late adulthood, the virus can reactivate to cause a number of neurologic conditions during a shingles outbreak. The Varicella-Zoster virus enters the body through the mouth, nose or through open skin. A persons mucous membranes such as the lining on the eyelids and eyeballs can also be an opening for the virus. Once inside the host, the virus attaches to the cells in the nose and lymph nodes and starts to reproduce. The virus then replicates and make its way to the persons spleen, liver, and sensory nerve tissues. As the virus replicates, it then starts infecting the cells in the skin. This skin infection prompts the blisters and rash that are the most noticeable symptom of the infection. The incubation period for the varicella virus is between 10-21 days. During this time a person maybe unaware of getting infected until a rash becomes visible. An infected person is contagious during the last one to two days of the incubation period before the rash breaks out. An infected person wouldn't be aware that he or she is contagious because of being asymptomatic. For this reason, chicken pox is highly contagious disease. Nine out of 10 non-immune people who live with someone with the varicella virus will catch it (health.howstuffworks.com, n.d.).
Role of Community Health Nurse
The first strategy for a nurse in dealing with chicken pox is to prevent the spread of the disease. Through direct contact with the blisters and the fluid inside the blisters, chicken pox can be spread instantly. Fluid from the blister can be left in clothing, bedding or dressings and can also cause an infection. Airborne droplets from a cough or sneezes of an infected person can easily spread chicken pox.. All nurses in contact with afflicted persons must always observe standard precautions and also wear gloves when performing dressing changes or changing the bed linens. A mask should also be utilized or have the patient wear a mask to prevent respiratory spread. Itching is one of the most annoying manifestations of chicken pox, and a patient who scratches the lesions may excoriate the skin or cause an infection from bacteria that get into the open lesions. For this reason it is recommended that you clip the patient’s fingernails short and encourage frequent hand washing. Nurses should also utilize antihistamines or soothing skin lotions such as calamine to a patients itching. Colloidal oatmeal or baking soda in a cool bath may also decrease itching and the patient can be instructed to utilize these as needed. The secondary complications of chicken pox include pneumonia, encephalitis and sepsis. Encephalitis is an inflammation of the brain, while sepsis is an overwhelming generalized infection. Any of these complications can be fatal. In addition to antiviral medications for chicken pox, the nurse will probably administer antibiotics and intravenous fluids for any identified complications. Aspirin should be avoided in this regimen due to the risk of Reye’s syndrome, a condition that causes inflammation in the brain and liver.
National Organization
The National Shingles Foundation nonprofit institution, and through their education and research, their main campaign is against the varicella-zoster virus and chickenpox, shingles and post-herpetic neuralgia. The organization is currently investigating the reasons for the virus' development and developing vaccines for prevention of shingles and chickenpox in the immunocompromised, and seek out new treatments for PHN pain (Litchfield, 2010). Costing $1.25 million, the organization has invested on research and development .
Conclusion
After the first occurrence, most people develop lifetime immunity to chickenpox and never experience it again. Unfortunately, the virus can sometimes come back later in life as shingles, with even harsher results. The current goal in the U.S. and many other countries is to provide universal immunization to children with the chicken pox vaccine. The chickenpox vaccine is administered in an early age and is part of a child's routine immunizations . The vaccine may also be given at any time if an older person has not had chickenpox. There have been few significant adverse reactions to the chickenpox vaccine. All children, except those with a compromised immune system, should have the vaccination to prevent an outbreak of this infection both early on and later in life.

References
Arvin, A. M. (1996). Varicella-zoster virus. Clinical microbiology reviews, 9(3), 361-381.
Chang, L. (2011, December 16). Epidemiological characteristics of varicella from 2000 to 2008 and the impact of nationwide immunization in Taiwan. Retrieved February 6, 2015, from http://www.biomedcentral.com/1471-2334/11/352
Feder, H. M. (1990). Treatment of adult chickenpox with oral acyclovir. Archives of internal medicine, 150(10), 2061-2065.
Gnann, J. W. (2002). Varicella-zoster virus: atypical presentations and unusual complications. Journal of Infectious Diseases, 186(Supplement 1), S91-S98.
Hambleton, S., & Gershon, A. A. (2005). Preventing varicella-zoster disease. Clinical microbiology reviews, 18(1), 70-80.
Litchfield, S. M. (2010). Shingles. AAOHN Journal, 58(6), 228-231.
Woodruff, A. W., & Wright, S. G. (2013). A synopsis of infectious and tropical diseases. Butterworth-Heinemann.