Major Bloodborne Pathogens: HIV, Hepatitis B, and Hepatitis C

The three most significant bloodborne pathogens in occupational and public health are:

1. Human Immunodeficiency Virus (HIV)

• Retrovirus; targets CD4⁺ T cells → AIDS.
• Transmission: blood, sexual, perinatal.
• Occupational risk: needlestick ~0.3%.
• PEP (post-exposure prophylaxis) within 72 hrs.
• No vaccine; ART suppresses, prevents transmission (U=U).

2. Hepatitis B Virus (HBV)

• DNA virus (hepadnavirus); causes acute/chronic hepatitis, cirrhosis, HCC.
• Highly infectious (100× HIV); survives on surfaces ≥7 days.
• Transmission: blood, sexual, perinatal.
• Occupational risk: needlestick 6–30% (if HBeAg+).
• Vaccine available (95% effective); HBIG + vaccine for PEP.
• Antivirals (entecavir, tenofovir) suppress replication.

3. Hepatitis C Virus (HCV)

• RNA virus (flavivirus); 70–85% chronic; leading cause of liver transplant.
• Transmission: blood (IDU, unsafe healthcare); sexual/perinatal less efficient.
• Occupational risk: needlestick ~1.8%.
• No vaccine.
• Curable: DAAs (sofosbuvir/velpatasvir, glecaprevir/pibrentasvir) → >95% SVR in 8–12 weeks.
• PEP: Not recommended; early treatment if seroconversion.

Universal Precautions

Treat all blood/body fluids as infectious. Engineering controls (safety devices), PPE, vaccination (HBV), prompt exposure reporting.