[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/