Biofilm formation on the surface of medical devices: a growing concern for hospital-acquired infections

Hospital-acquired infections (HAIs) are nosocomial infections or diseases that are contracted during medical care but were absent at admission. Usually resulting from biofilm development on device surfaces, these infections shield microorganisms and raise their resistance to antimicrobial therapies. Moreover, many infections are challenging to detect and treat, which raises morbidity, death, and medical expenses. On medical equipment, biofilms, which are dense microbial colonies surrounded by an extracellular matrix, have been reported to be a major cause of ongoing infections resistant to antibiotics and human immune responses. Up to 75% of all bacterial infections are associated with biofilms, which also significantly contribute to nosocomial infections, especially in intensive care units. Common device-associated infections include catheter-related bloodstream infections, urinary tract infections, and ventilator-associated pneumonia. Both bacterial and fungal pathogens cause these diseases; however, the multi-species biofilms of bacterial and fungal pathogens provide extra treatment difficulty. Common bacteria such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, as well as fungal pathogens like Candida albicans, can form biofilms on various devices, including catheters, prosthetic joints, and ventilators. Most of the time, traditional treatment therapies fail. Therefore, device removal and long-term antibiotic treatment become necessary. The development of new strategies for prevention and treatment, including innovative anti-adhesive coatings and nanomaterial-based techniques targeting biofilm formation stages, the application of biofilm-active antibiotics, anti-quorum sensing agents, and biofilm dispersal agents has attracted attention in recent years. Here, we discuss the latest developments in relation to several strategies, such as antimicrobial coating, surface modification, nanostructured surface and nanomaterials, and the incorporation of regulatory molecules (natural and synthetic molecules) to prevent biofilms on the surface of biomedical devices.