Being a new member, I am not permitted to post website links yet so I will try to guide you:
It used to have its dedicated page with a long list of requirements (page is no longer there), the website link was mentioned by Flyin'Dutch' on this forum under the thread number 409787 if you can retrieve it. An archived snapshot by a third party site from July 2018 can be found online...
Currently the only information about it is covered by a few general paragraphs, if you search "CAA HIV" on Google it should be at the top of the page...
I am just curious to know if the CAA decided to simply hide it for some reason or if there has been any change in the requirements...