What type of viruses can be classified as bloodborne pathogens?

Bloodborne pathogens are specifically defined as microorganisms in the blood that can cause disease in humans. This classification primarily includes certain viruses—the most notable examples being HIV (human immunodeficiency virus) and hepatitis viruses such as HBV (hepatitis B virus) and HCV (hepatitis C virus). These viruses are able to be transmitted through direct contact with infected blood, making them a significant concern in healthcare settings and situations involving potential exposure to bodily fluids.

The other options present different types of microorganisms that do not fall under the strict definition of bloodborne pathogens. Bacteria and fungi, while they can be pathogenic, do not primarily transmit infections through blood. Parasites, on the other hand, typically have different modes of transmission and are not classified as bloodborne pathogens either. Thus, the option identifying "viruses that infect through blood" is the correct one, as it accurately encapsulates the essence of bloodborne pathogens.