Question

describe the characteristics of virus responsible for respiratory viral infection, herpes infection,CMV, HIV/AIDS. How do drugs used to destroy viruses work to control disease

Answer 1

Ans)A h virus is a small infectious organism—much smaller than a fungus or bacterium—that must invade a living cell to reproduce (replicate). The virus attaches to a cell (called the host cell), enters the cell, and releases its DNA or RNA inside the cell. The virus’s DNA or RNA is the genetic material containing the information needed to make copies of (replicate) the virus. The virus’s genetic material takes control of the cell and forces it to replicate the virus. The infected cell usually dies because the virus keeps it from performing its normal functions. When it dies, the cell releases new viruses, which go on to infect other cells.

Viruses are classified as DNA viruses or RNA viruses, depending on whether they use DNA or RNA to replicate. RNA viruses include retroviruses, such as HIV (human immunodeficiency virus). RNA viruses, particularly retroviruses, are prone to mutate.

Some viruses do not kill the cells they infect but instead alter the cell's functions. Sometimes the infected cell loses control over normal cell division and becomes cancerous.

Some viruses, such as hepatitis B virus and hepatitis C virus, can cause chronic infections. Chronic hepatitis can last for years, even decades. In many people, chronic hepatitis is quite mild and causes little liver damage. However, in some people, it eventually results in cirrhosis (severe scarring of the liver), liverfailure, and sometimes liver cancer.

- Viruses are structurally different from bacteria. The antibiotic has no “target” to attack in a virus. However, antiviral medications and vaccines are specific for viruses. Vaccines stimulate your own immune system to produce antibodies, which then can “recognize” the virus to inactivate it before it can cause disease.