Anyway, in answer to your question on whether I am sure CBD helps: No.
I read one good-quality paper that reported an effect, and suggested plausible mechanisms. But the authors cautioned it needed more work before it could be recommended clinically. In particular, there was no hint it might prevent infection, or be useful to treat mild cases. The perhaps surprising bit was that THC interfered with the effect of the CBD.
The US NIH says that fluvoxamine is useful to treat serious cases. Any doctor can prescribe that.