Evaluate the following distinct patient encounters involving recent exposures to infectious agents. Match each patient scenario to the most appropriate, guideline-based post-exposure prophylaxis (PEP) or vaccine intervention.
- A 28-year-old primigravid woman at 30 weeks gestation, with a negative varicella IgG titer, who had face-to-face contact with a child diagnosed with chickenpox 3 days ago.Administer Varicella-zoster immune globulin (VZIG) only.
- A healthy 10-month-old infant who spent two hours in a waiting room with a patient later confirmed to have measles, with the exposure occurring 48 hours ago.Administer the Measles-Mumps-Rubella (MMR) vaccine.
- A nurse with documented non-responder status to the Hepatitis B vaccine series (anti-HBs < 10 mIU/mL after 6 total doses) who sustained a deep needlestick injury from an HBsAg-positive patient.Administer Hepatitis B immune globulin (HBIG) immediately and repeat in one month.
- A 45-year-old man who sustained a deep, soil-contaminated puncture wound to his foot; he received only two doses of a tetanus toxoid-containing vaccine during his childhood.Administer Tdap vaccine and Tetanus immune globulin (TIG).
Answer
Match the pregnant varicella exposure to VZIG; the infant measles exposure to the MMR vaccine; the Hepatitis B non-responder to two doses of HBIG; and the incomplete tetanus series with a dirty wound to Tdap plus TIG.
Each patient's clinical profile directly dictates the specific immunological mechanism required for protection: passive immunity when active vaccines are contraindicated or ineffective (pregnancy, vaccine non-responders), early active immunity for rapid-onset protection (measles in infants), or combined active-passive immunity for high-risk toxoid exposures (tetanus).
Step-by-Step Solution
Key Concept
Post-exposure prophylaxis depends heavily on the pathogen, the time elapsed since exposure, and host factors such as age, pregnancy status, immune competence, and prior vaccination history.
Estimated Time:1m 30s