Vaccines and Serums: Treatment vs. Prevention After Infection

No. Vaccines and immune serums (immunoglobulins) are preventive tools—they stimulate immunity before exposure or very early after. Once a disease is established, vaccination is ineffective for that illness.

Treatment of active infection requires disease‑specific therapies: antivirals, antibiotics, supportive care, etc. Post‑exposure prophylaxis (e.g., rabies vaccine + immunoglobulin) is a narrow exception given immediately after known exposure, before symptoms start.