Oral HCP and patients can be exposed to bloodborne pathogens and other pathogenic microorganisms These organisms can be transmitted in dental settings from patient-to-patient, patient-to-provider, and provider-to-patient through contact with infected blood and OPIM; inhalation of droplets and droplet nuclei generated when infected persons cough, sneeze, shout, sing, or talk; and less frequently by contact with freshly contaminated articles and environmental surfaces.

When acutely ill with many of the infections discussed, patients do not usually seek routine dental outpatient care. Nonetheless, a general understanding of the diseases, their clinical features, and preventive and therapeutic strategies is critical because some oral HCP are hospital-based; some infected patients may be unaware of their infectious status and seek urgent/elective care in outpatient dental offices; and oral HCP might become infected with these pathogens.

In addition, while Standard Precautions apply to contact with blood and OPIM, nonintact skin, and mucous membranes, other measures (e.g., expanded standard precautions or transmission-based precautions) might be necessary to prevent the spread of certain pathogenic organisms (e.g., TB disease influenza, and varicella). This requires that oral HCP be familiar with the modes of transmission of all pathogens potentially encountered in oral healthcare settings.