[niknoble]

Apparently the CDC literally changed its definition. From the Miami Herald (but you can check against other sources):

> Before the change, the definition for “vaccination” read, “the act of introducing a vaccine into the body to produce immunity to a specific disease.” Now, the word “immunity” has been switched to “protection.” The term “vaccine” also got a makeover. The CDC’s definition changed from “a product that stimulates a person’s immune system to produce immunity to a specific disease” to the current “a preparation that is used to stimulate the body’s immune response against diseases.”

Webster dictionary broadened its definition too. From USA Today:

> Merriam-Webster revised its "vaccine" definition to replace "immunity" with "immune response."

[epakai]

What were non-immunizing vaccines called before? I've seen "intramuscular virus injection", but I don't think that was ever a layman's term.

Have we not always had the concept of sterilising immunity, and therefore non-sterilising immunity?

To me this is just nuance being exposed, and word definitions being updated to include that nuance.

[the_third_wave]

They were called "non-immunising vaccines". viz. this article from 2001:

Development of a non-immunising, paraspecific vaccine from attenuated pox viruses: a new type of vaccine

https://pubmed.ncbi.nlm.nih.gov/12578306/