I was informed by my teacher that this retrovirus changes its RNA, so there is not a drug which can recognize the RNA and somehow inactivates it. Are there any other reasons explaining why there isn't a vaccine for the HIV?
$\begingroup$ That's a good answer, and I'd say it's a duplicate. $\endgroup$– De NovoJul 30, 2018 at 22:14
1$\begingroup$ On review, I see this question is asking for other reasons, as well as the antigenic variability. I'll undelete my answer. $\endgroup$– De NovoJul 31, 2018 at 4:46
One of the reasons we don't have an HIV vaccine yet is we've only been trying to make one for a little over 30 years. It can take a long time to develop a vaccine. Beyond that, there are a number of specific challenges.
One of them is that, yes as your teacher said, the virus is highly variable. Specifically, the parts of the viral proteins involved in binding and infecting a host cell are highly variable. There are a number of other challenges. One important and related challenge is that, unlike with many vaccine preventable diseases (e.g., measles), an successful HIV vaccine will have to entirely prevent infection rather than just control and clear infection without developing disease. Once a reservoir of infected cells is established, the opportunity for clearance is gone. This makes the production and maintenance of high titers of neutralizing antibodies that much more important.
There is a very good review of the challenges and current directions of HIV vaccine development here
$\begingroup$ "Once a reservoir of infected cells is established, the opportunity for clearance is gone." So with current advances crispr to cut out the established DNA is a good idea? (and not just me being spontanous (as I don't remember if I remember, sorry...):):-) Thank you. $\endgroup$ Nov 16, 2020 at 17:07
$\begingroup$ Also, it'd be interesting to hear about a general principle of antibody vaccinaton not being fast enough - with aids, it's the establishment in the genome that has advantage, in case of Covid the equivalent would be infectivity, i.e. if antibodies are too late the person might not get sick ut it will spread the virus for a while, before antibodies get to grips and stop the replication. That's correct? $\endgroup$ Nov 16, 2020 at 17:25