True. There have been many COVID vaccines that worked in mice, but not as well in humans. The early coronavirus vaccines worked really well in orangutans, well enough to prevent other orangs in the same cage from getting sick.

There are at least 44 intra-nasal vaccines in pre-clinical development.[1] Something is probably going to work.

[1] https://medicalxpress.com/news/2023-04-potential-mucosal-cov...