Examples of Live Vaccinations
Live vaccines contain attenuated but replicating viruses or bacteria that induce immunity through a low-grade infection in healthy individuals, and include measles-mumps-rubella (MMR), varicella, rotavirus, yellow fever, herpes zoster (Zostavax), live attenuated influenza vaccine (LAIV), BCG, and oral typhoid (Ty21a). 1, 2
Live Viral Vaccines
- MMR (Measles, Mumps, Rubella) is a widely used live attenuated vaccine providing protection against three viral diseases 2
- Varicella (Chickenpox) vaccine prevents primary varicella infection and is recommended for routine childhood immunization 2
- Rotavirus vaccine is an oral vaccine for prevention of severe diarrheal disease in infants 2
- Yellow fever vaccine is used for prevention in travelers to endemic areas 2
- Zoster vaccine live (ZVL/Zostavax) prevents herpes zoster in older adults, though it has been largely replaced by the recombinant vaccine Shingrix due to superior efficacy 2
- Live attenuated influenza vaccine (LAIV) is administered as a nasal spray for children and adults 2
- Oral poliovirus vaccine (OPV) contains three attenuated strains, though it carries a small risk of vaccine-associated paralysis (2 per 1,000) and is no longer used in many countries 1, 3
- Smallpox vaccine is a live vaccine used in specific circumstances 1
Live Bacterial Vaccines
- BCG (Bacille Calmette-Guérin) is used for tuberculosis prevention in high-risk populations 2
- Ty21a Salmonella Typhi is an oral typhoid vaccine for travelers to endemic areas 2
Critical Safety Considerations
- Live vaccines are contraindicated in patients with severe immunodeficiency including SCID, complete DiGeorge syndrome, HIV/AIDS with severe immunosuppression, and active malignancy on immunosuppressive therapy 2
- Patients with severe T cell deficiencies should not receive any live viral or bacterial vaccines prior to immune reconstitution 1
- Patients with chronic granulomatous disease and IFN-γ-IL-12 pathway defects should not receive BCG or Salmonella Ty21a due to predilection for these infections 1
- Live vaccines are generally contraindicated during pregnancy due to theoretical risk to the fetus 2
- Close contacts of immunocompromised patients should not receive oral polio vaccine due to viral shedding risk, but may receive other live vaccines like MMR and varicella as shedding is unlikely 1
Administration Guidelines
- When administering multiple live vaccines, they should either be given on the same day or separated by at least 4 weeks to ensure adequate immune response 2
- If two live parenteral vaccines are administered less than 4 weeks apart, the second vaccine dose should be repeated after waiting at least 4 weeks from the invalid dose 2
- Immune globulin administration may impair live vaccine efficacy, requiring deferral of live virus vaccination until approximately three months after immune globulin administration 4