CPT code 90393 identifies Vaccine Immune Globulin (VIg), a human plasma–derived antibody product collected from donors repeatedly vaccinated against smallpox. Nationally, this code is significant for public health preparedness and for clinicians managing exposures or high-risk patients requiring passive immunization against smallpox. Use of VIg is typically limited to specialized settings and events where smallpox exposure is suspected or for prophylaxis in defined clinical scenarios.

Key payers addressed in this overview include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication outlines payer coverage patterns, where available, and places the code in clinical and policy context relevant to national immunization and biodefense planning.

Readers will learn what CPT code 90393 represents, the clinical situations in which VIg is used, the typical sites of service for administration, and which major payers are commonly involved in coverage discussions. The summary also indicates where input data was unavailable. This information supports coding accuracy, billing workflows, and coordination between clinical teams and payers for the administration of passive immunotherapy against smallpox.