What term refers to pathogens present in blood that cause diseases in humans?

The term that refers to pathogens present in blood that cause diseases in humans is bloodborne pathogens. These are microorganisms such as viruses, bacteria, and parasites that are transmitted through direct contact with infected blood or other potentially infectious materials. Common examples of bloodborne pathogens include the human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Understanding this concept is critical in infection control, particularly in settings such as dental practices where exposure to blood is possible.

In contrast, airborne pathogens are those that are transmitted through the air, often via respiratory droplets; waterborne pathogens are associated with contaminated water sources; and vectorborne pathogens are spread by vectors like insects. Each of these categories represents a different mode of transmission, which is key to developing appropriate infection control strategies tailored to specific risks.