Which route of transmission involves contact with contaminated instruments?

Indirect transmission involves the transfer of infectious agents through contaminated objects or surfaces, which is exactly what happens when there is contact with contaminated instruments. In a dental setting, instruments that have not been properly sterilized can harbor pathogens, and when they come into contact with a patient's mucous membranes or open wounds, transmission can occur.

This route of transmission is significant in infection control because it emphasizes the importance of rigorous sterilization and disinfection protocols to prevent the spread of infections. Safe practices, including proper cleaning, sterilizing, and handling of dental instruments, are crucial in minimizing the risk of indirect transmission among patients and dental healthcare providers.

Other routes listed, such as vector-borne, airborne, and direct transmission, involve different mechanisms of disease transfer and do not specifically refer to the risks associated with contaminated instruments.