An HIV-positive patient with a CD4 count of 150 cells/µL requests a measles-mumps-rubella (MMR) vaccine (live attenuated). Based on safety considerations, which is the best evidence-based recommendation?

• A. Administer the MMR vaccine immediately because measles disease risk outweighs any potential risk of replication from the attenuated vaccine in someone with any degree of immunosuppression.
• B. Defer the live attenuated MMR vaccination until immune reconstitution is achieved (CD4 count sufficiently recovered), and consider serologic testing and alternative strategies rather than administering the live vaccine now due to risk of vaccine-associated disease.
• C. Advise immediate passive immunization with pooled maternal IgG rather than attempt any active immunization because passive immunity is long-lasting and superior to live vaccines in immunosuppressed adults.
• D. Recommend two doses of high-titer inactivated MMR substitute immediately in place of the live vaccine since a licensed inactivated MMR vaccine is always equivalent in immunity and safety profile.

Answer: (B)