A viral infection is a proliferation of a harmful virus inside your body. Viruses cannot reproduce without the assistance of a host. Viruses infect a host by introducing their genetic material into the cells and hijacking the cell's internal machinery to make more virus particles.

For most viral infections, treatments can only help with symptoms while you wait for your immune system to fight off the virus. Antibiotics do not work for viral infections. There are antiviral medicines to treat some viral infections. Vaccines can help prevent you from getting many viral diseases. The most common respiratory infections are upper respiratory infections, which include sore throat, sinusitis, and the common cold. Other viral respiratory infections include influenza, pneumonia, and coronaviruses.

Viral diseases are extremely widespread infections caused by viruses, a type of microorganism. There are many types of viruses that cause a wide variety of viral diseases. The most common type of viral disease is the common cold, which is caused by a viral infection of the upper respiratory tract (nose and throat). Other common viral diseases include:

• Chickenpox
• Flu (influenza)
• Herpes
• Human immunodeficiency virus (HIV/AIDS)
• Human papillomavirus (HPV)
• Infectious mononucleosis
• Mumps, measles and rubella
• Shingles
• Viral gastroenteritis (stomach flu)
• Viral hepatitis
• Viral meningitis
• Viral pneumonia

Viral diseases are contagious and spread from person to person when a virus enters the body and begins to multiply. Common ways that viruses spread from person to person include:

• Breathing in air-borne droplets contaminated with a virus
• Eating food or drinking water contaminated with a virus
• Having sexual contact with a person who is infected with a sexually transmitted virus
• Indirect transmission from person to person by a virus host, such as a mosquito, tick, or field mouse
• Touching surfaces or body fluids contaminated with a virus

Viral diseases result in a wide variety of symptoms that vary in character and severity depending on the type of viral infection and other factors, including the person’s age and overall health. Common symptoms of viral diseases include flu-like symptoms and malaise.

Viral diseases are not treatable with antibiotics, which can only cure bacterial diseases and infections. However, the most common viral diseases, the common cold and the flu, are self-limiting in generally healthy people. This means that the viral infection causes illness for a period of time, then it resolves and symptoms disappear as your immune system attacks the virus and your body recovers.

Media Contact
David Paul
Managing Editor
Journal of Infectious Diseases and Diagnosis