Recombinant live vaccine

The first vaccine was for smallpox. Edward Jenner used cowpox pus to create immunity. Notable subsequent vaccines include polio, flu (influenza), hepatitis A and B, measles, rotavirus, and pneumococcal disease. Live vaccines include live attenuated (MMR-II), rVSV-ZEBOV vaccine (Ebola), and live recombinant vaccines. == Features / Mechanisms ==

Using a mechanism similar to infections that occur naturally, live recombinant vaccines can generate immunity that is robust and long-lasting. There are currently no widely deployed live recombinant vaccines. == Clinical Use ==

Research Recombinant vaccines causing protein, viral vectors and conjugates are under research. Research is searching for better Streptococcus vaccines. Existing polyvalent vaccines protect against as many as 23 serotypes, but need to address the entire set of 100 serotypes. In 2021, 2 vaccines were launched by Pfizer and Merck: Prevnar 20 (PCV-20) and Vaxneuvance (PCV-15), respectively. Vaxneuvance covers 5 fewer serotypes, but the combination of Pneumovax 23 with Vaxneuvance covers more serotypes than Prevnar20. Vaccines are heading for stronger protection against known serotypes, but also attack other strains or serotypes. == Precautions ==

While live recombinant vaccines are generally considered to be safe, genetically modified organisms can potentially revert to pathogenic modes, causing disease, particularly in young, immunocompromised and/or older subjects. == References ==