The eye is well protected from infection by the conjunctiva and the corneal epithelium. In addition, the tear film contains antimicrobials while the tear flow itself tends to wash away pathogens. The eye also harbors a host of non-pathogenic bacteria that competitively prohibit new bacteria growth. However, these eye-defenses can be breached by trauma, improper tearing, or contact lens wear and lead to an infection. An eye infection not only threatens vision, but the orbit can act as an entry portal to the rest of the body and infections can progress to systemic involvement, meningitis, and even death.
