The correct answer is D, "Hepatitis B immune globulin (HBIG) and hepatitis B vaccine," as this is the recommended regimen for an HBsAb-negative employee with a percutaneous exposure to blood from an HBsAg-positive patient. According to the Certification Board of Infection Control and Epidemiology (CBIC) guidelines, which align with recommendations from the Centers for Disease Control and Prevention (CDC) and the Advisory Committee on Immunization Practices (ACIP), post-exposure prophylaxis (PEP) for hepatitis B virus (HBV) exposure depends on the employee’s vaccination status and the source’s HBsAg status. For an unvaccinated or known HBsAb-negative individual (indicating no immunity) exposed to HBsAg-positive blood, the standard PEP includes both HBIG and the hepatitis B vaccine. HBIG provides immediate passive immunity by delivering pre-formed antibodies, while the vaccine initiates active immunity to prevent future infections (CBIC Practice Analysis, 2022, Domain III: Infection Prevention and Control, Competency 3.2 - Implement measures to prevent transmission of infectious agents). The HBIG should be administered within 24 hours of exposure (preferably within 7 days), and the first dose of the vaccine should be given concurrently, followed by the complete vaccine series.

Option A (immune serum globulin and hepatitis B vaccine) is incorrect because immune serum globulin (ISG) is a general immunoglobulin preparation and not specific for HBV; HBIG, which contains high titers of anti-HBs, is the appropriate specific immunoglobulin for HBV exposure. Option B (hepatitis B immune globulin [HBIG] alone) is insufficient, as it provides only temporary passive immunity without initiating long-term active immunity through vaccination, which is critical for an unvaccinated individual. Option C (hepatitis B vaccine alone) is inadequate for immediate post-exposure protection, as it takes weeks to develop immunity, leaving the employee vulnerable in the interim.

The recommendation for HBIG and hepatitis B vaccine aligns with CBIC’s emphasis on evidence-based post-exposure management to prevent HBV transmission in healthcare settings (CBIC Practice Analysis, 2022, Domain III: Infection Prevention and Control, Competency 3.1 - Collaborate with organizational leaders). This dual approach is supported by CDC guidelines, which prioritize rapid intervention to reduce the risk of seroconversion following percutaneous exposure (CDC Updated U.S. Public Health Service Guidelines for the Management ofOccupational Exposures to HBV, HCV, and HIV, 2013).