Which term describes an infection in which only the genetic message is present in the host, with no viable organisms?

• A. Subclinical
• B. Latent infection/disease
• C. Clinical infection
• D. Persistent infection

Answer: (B)

Latent infection describes a state where the pathogen’s genome persists in host cells, but there is no active replication and no production of infectious virus particles. In this situation the host carries only the genetic message, not viable organisms, so there are no symptoms or transmission from the latent phase until reactivation occurs. This fits the idea of having the genetic material present without any viable virus being produced.

Subclinical infection means the infection is present without noticeable symptoms, but viable virus and replication can still occur, so it isn’t necessarily just genetic material alone. Clinical infection involves symptoms with active disease and ongoing viral replication. Persistent infection implies ongoing presence and production of viable virus over time.