Varicella zoster virus
A Microbial Biorealm page on the genus Varicella zoster virus
Classification
Order: Herpesvirales; Family: Herpesviridae; Subfamily: Alphaherpesvirinae; Genus: Varicellovirus; Species: Human herpesvirus 3; Commonly known as Varicella Zoster Virus (VZV)
Description and significance
The isolation of Varicella Zoster Virus was first published in 1958. This virus is the causative agent of chicken pox, a disease characterized by a blister-like rash on the skin and often accompanied by fever. This disease is highly contagious, transmitted by sneezing or coughing, direct contact, or aerosol transmission of virus from skin lesions. This is known as varicella.
After recovering from the varicella disease, a person may develop shingles, also known as zoster or herpes zoster, due to the virus remaining in the dorsal root ganglia. Shingles is characterized by a painful rash on one side of the body, typically preceeded by pain, itching, or tingling in that area. It may also be accompanied by fever, headache, chills, or upset stomach. The risk of developing shingles increases with age, especially after 50 years of age. Almost 1 out of every 3 Americans will develop shingles, and 1 million cases are estimated to occur in this country each year.
Disease caused by the Varicella Zoster Virus can be prevented by the varicella vaccine; two doses of the vaccine are recommended. People who have been vaccinated may still get the disease, but if they do it will be milder, and there is a much lower chance of such infection. Before the vaccine became widely available, an estimated 4 million cases of varicella occured each year in the U.S.; rates have decreased by 53-88% as of 2004.
Genome structure
Describe the size and content of the genome. How many chromosomes and plasmids? Circular or linear? Other interesting features? What is known about its sequence?
Cell structure, metabolism & life cycle
Provide a physical and biochemical description of the organism. What kind of organism is it, what does it look like, how is it built, what are its metabolic properties, how can it be identified, what is it's life cycle, &c. In other words, describe the organism from its perspective.
Ecology (including pathogenesis)
Describe its habitat, symbiosis, and contributions to environment. If it is a pathogen, how does this organism cause disease? Human, animal, plant hosts? Describe virulence factors and patient symptoms.
Interesting feature
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References
International Committee on Taxonomy of Viruses. Accessed October 31, 2011. "Varicella-Zoster Virus Infection" National Center for Infectious Diseases. Page last reviewed July 14, 2011. Accessed October 31, 2011.
