What is a systemic infection?

A systemic infection is characterized as one that has spread throughout the body, rather than being confined to a single organ or area. This type of infection typically involves the bloodstream and can affect multiple body systems, making it more serious and harder to treat than localized infections. When pathogens enter the bloodstream, they can travel to various parts of the body, leading to a widespread inflammatory response and symptoms that can impact many systems, such as fever, fatigue, and malaise.

In contrast, localized infections are restricted to one area, nonpathogenic organisms do not typically cause disease, and systemic infections usually do present symptoms indicative of a body-wide response to infection. Thus, the definition of a systemic infection fundamentally revolves around its nature of distribution and systemic impact.