Virus carriers are people who carry a virus without clinical symptoms or histopathologic damage. Viral carriers are those who are infected with the appropriate virus but do not show clinical symptoms. Virus carriers are generally targeted at viruses that tend to cause chronic diseases, such as hepatitis B virus and HIV. Hepatitis B carriers are people who are positive for the hepatitis B virus, but no obvious damage to the liver can be found through liver function tests and ultrasound. HIV carriers are those who have tested positive for HIV but have not entered the AIDS stage, causing no clinical symptoms or histologic damage. It is important to note that carriers of the virus also have a large amount of the virus in their bodies and are still contagious. Virus carriers may have further progression of their disease and also need regular check-ups.