APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -Chronic infection is characterized by the continued presence of infectious virus following the primary infection and may include chronic or recurrent disease. Slow infection is characterized by a prolonged incubation period followed by progressive disease.

Detailed explanation-2: -Persistent infections are where the viruses are continually present in the body. In a latent viral infection the virus remains in equilibrium with the host for long periods of time before symptoms again appear, but the actual viruses cannot be detected until reactivation of the disease occurs.

Detailed explanation-3: -Slow infections are ones in which the infectious agents gradually increase in number over a very long period of time during which no significant symptoms are seen. Examples include AIDS (caused by HIV-1 and HIV-2) and certain lentiviruses that cause tumors in animals.

Detailed explanation-4: -Persistent infections do not have to be rapidly spreading-or even in an active period of growth-in order to be classified as such. There are three categorizations of persistent infection: chronic, latent, and slow. A chronic infection is one that can eventually be eradicated.

Detailed explanation-5: -A chronic infection is a type of persistent infection that is eventually cleared, while latent or slow infections last the life of the host. There is no single mechanism responsible for establishing a persistent infection; a key feature is reduction in host defenses and the ability of the virus to kill cells.