It seems hard to believe but the last time I wrote about the bivalent Covid 19 vaccine was October of 2022. A lot has changed since then but I still get many questions about when to get the vaccine? Should I get the vaccine or which vaccine should I get? New data and recommendations are always coming out and I thought that it was time to revisit this issue.

First, the new data about how much additional protection the bivalent vaccine offers compared to the original is interesting. Remember, the bivalent vaccine was developed when the Omicron strain of virus was the leading virus strain and it was felt that a specific vaccine addressing Omicron along with the original strain was needed. Because the mRNA technology used to make the vaccine allows for rapid development the new bivalent vaccine which addressed both the original virus and Omicron was brought into the market rapidly.

Pfizer and Moderna, the two main vaccine producers for the US, both presented data which showed that the new bivalent vaccine did not really increase the immunity to Omicron that was anticipated. The increase in immunity developed by the bivalent vaccine was only 1.5 to 1.75 times the immunity developed by the original or monovalent vaccine. However, the protection from severe disease remained unchanged.

What is the take away at this time? It does not appear to matter which vaccine you get monovalent or bivalent the protection is the same. At risk patients should get it annually.