In what way do biofilms contribute to infection persistence?

Biofilms significantly contribute to infection persistence primarily by providing a protective matrix for bacteria. This matrix is composed of extracellular polymeric substances (EPS) that are secreted by the bacteria within the biofilm. The EPS creates a shield around the microbial community, which not only serves as a physical barrier against host immune cells but also protects the bacteria from the effects of antibiotics and other antimicrobial agents.

In chronic infections, bacteria within biofilms exhibit enhanced resistance to treatments due to this protective environment, as the matrix can hinder the penetration of antibiotics. Additionally, the microorganisms within a biofilm can undergo changes in gene expression, allowing them to adopt a more persistent lifestyle, often leading to a state of dormancy or slowed metabolism, further enhancing their survival.

The presence of biofilms can complicate treatment and contribute to the recurrence of infections, as the bacteria can detach from the biofilm and spread to other sites, leading to new infections. This adaptability and resilience are key factors in the persistence of infections associated with biofilms.