Bacterial or Viral Infection
Bacterial and viral infections may look and seem similar when you get sick. Both types are caused by microbes and spread by things such as:
Contact with infected people, especially through kissing.
Contact with contaminated surfaces.
Ingesting contaminated products.
Contact with infected creatures, including pets, livestock, and insects such as fleas and ticks.
Both infections can lead to symptoms ranging from mild to severe and should be treated by a health care professional. In some cases, it's difficult to determine whether an illness is viral or bacterial because many ailments -- including pneumonia, meningitis, and diarrhea -- can be caused by either. Medical professionals may be able to determine the cause by doing a physical exam and conducting tests to determine the best way to treat your illness.
While antibiotics can be used to treat most bacterial infections, they do not have any effect on viral infections. Vaccines have proven effective against and drastically reduced the spread of viral infections, such as measles, flu and hepatitis.