WE NEED YOUR HELP!
Please donate to keep ReaderRant online to serve political discussion and its members. (Blue Ridge Photography pays the bills for RR).
Colds actually have many many different strains, but none of them are retroviruses. A retrovirus inserts it's own DNA analog into the host nucleus, so the host cells make more virus RNA. The best example of a retrovirus is HIV. Yes, it's very difficult to make a vaccine for that.
We can make cold vaccines quite easily. It's decades-old technology. And they work fine. BUT (and it's a huge but) they only work against that strain. There are a hundred+ other strains that will cause more colds. In fact we sort of do that, by making antibodies against a strain we catch. Then we can't catch that strain for a while, a few years to a lifetime. So it's not that we can't make such a vaccine: It's just useless and making it would have no return on investment.