Microbiology Practice Exam

What type of virus is Varicella-zoster?

1. RNA virus

2. DNA virus

3. Retrovirus

4. Protein virus

The correct answer is: DNA virus

Varicella-zoster virus (VZV), responsible for chickenpox (varicella) and shingles (herpes zoster), is classified as a DNA virus. Specifically, it belongs to the Herpesviridae family, which is characterized by having a double-stranded DNA genome. This classification is significant because DNA viruses typically replicate in the nucleus of the host cell, utilizing the host's cellular machinery to synthesize and assemble new viral particles. Understanding the type of virus is crucial for grasping the mechanisms of infection and disease transmission, as well as the development of vaccines and antiviral treatments. For instance, live attenuated vaccines are utilized to prevent the initial chickenpox infection, reducing the incidence of both diseases related to the virus. The other classifications, such as RNA viruses, retroviruses, and protein viruses, do not apply to VZV. RNA viruses contain RNA rather than DNA and may replicate in the cytoplasm, while retroviruses, like HIV, replicate through a reverse transcription process from RNA to DNA. Protein viruses are a less commonly used term and typically refer to viruses that rely mainly on their protein coat for function and do not encapsulate genetic material. Understanding these distinctions is vital for studying viral pathology and developing appropriate therapeutic