Which pathogens pose the greatest risk in bloodborne transmission?

• A. HIV, Hepatitis A and E
• B. HIV, Hep B and C
• C. Ebola, Zika, and Dengue
• D. Herpes Simplex and HPV

Answer: (B)

The key idea is identifying pathogens that are efficiently transmitted through blood and are most likely to spread via blood exposures in healthcare or other settings. HIV, hepatitis B, and hepatitis C fit this best because they are highly transmissible through blood or blood products and are common concerns with needlestick injuries or shared needles. Hepatitis B is extremely infectious; even small amounts of infected blood can transmit the virus, and vaccination provides a preventive option. Hepatitis C is also primarily bloodborne and often leads to chronic infection, while HIV remains a major bloodborne risk with potential for occupational exposure.

Hepatitis A and E are mainly spread through contaminated food or water (fecal-oral), not through blood. Ebola, Zika, and Dengue involve blood in transmission but are not the routine, ongoing bloodborne risks in typical settings—Dengue and Zika are vector-borne, and Ebola outbreaks involve exposure to bodily fluids but are less representative of everyday bloodborne risk. Herpes simplex and HPV are transmitted mainly through close contact or sexual transmission, not through blood in the usual sense.