So i was vampire happy as little kid... since about lvl 5 till about lvl 70?... after 300 something gameplay hours decided its time to do guilds and finish story. so went and became werewolf... yawned and sighed... no spells, no abilities, no gear, illusion spells go back to being utterly useless and so on... finished everything related to companions and decided thats enough for me of werepup... cured it. Now i cant get vampism AT ALL. Even adding disease through console just says spell got added but its not in effects no amount of standing naked getting hammered by 4 volkihar master vampire amounts to anything... did i just run into yet another bug? im getting tired of this.
its baffling that you still cant conjure anything other then weapons if you have spell absorption... and thats after what? 8 patches?...
So anyone got any ideas?...

game is glitchy to no end... since the logical way doesnt work.

how to add a disease via console. attempts to player.addspell b8780 result in just message that it was added but its not in effects and nothing is changed applies to all diseases actually.
No im not a werewolf it was cured. best guess somewhere at some point game as always forgot to uncheck something so now im permanently screwed from doing things the normal way.
was vampire for about 300 hours or so... changed to werewolf for purpose of doing companions quest line... as soon as i was fully done ran like the wind to get my vampirism back... and tada! screwed by ever so buggy game >_>

Adding diseases via consoles is similar to actually contracting them in that a random number must be checked to see if you actually contract the disease. The odds of contracting Sanguinare Vampiris are 1 in 10, so I'd just try the command and keep checking your diseases menu.

Enchant a Item Via PC with the Bloodthirst spell and then equip it

Also if ur on console, I heard that the 1 in 10 actually starts the moment they cast the spell, so to up ur chance Los the vamps so that they are constantly recasting, ull get it in no time.