Blood Infusion

Get hit by Blood Mirror and bite three times, that's it.

I have completed this quest as of 6.0.2, so I would like to give some input.

My group was comprised of a Warrior (myself), a Restoration Druid, and two others, who were only there to get bitten. Make sure that you have Shadow's Edge equipped.

Here's how I did it.

At the start of the fight, everyone else stayed at the entrance of the room. I attacked Blood-Queen Lana'thel by myself, without any heals. After a few seconds, I gained Blood Mirror, and a few seconds later, she bit me, giving me Essence of the Blood Queen and my first stack of Gushing Wounds. At this point, you can start receiving heals, but there is no reason for anyone else to be attacking the boss.

It takes one minute for Essence of the Blood Queen to allow you to cast Vampiric Bite on another player. After biting the first player, you receive a second stack of Gushing Wounds.

I chose to bite the mage in my group first. I discovered that Blood Mirror links to the character closest to you, so after biting the mage, I stayed very close to her, with my back to the boss so that I would not dodge or parry, and the mage stood in the Swarming Shadows. All of these allowed her to die very quickly, so that she would no longer have Essence of the Blood Queen. Once she died, the druid cast Rebirth, and the mage came back to life.

After the second minute, the boss casts Incite Terror, and directly after, Bloodbolt Whirl. The group then used a few defensive cooldowns in order to survive this phase, as it dealt the most damage.
At about the same time, I was able to cast my second Vampiric Bite, which I used on the rogue, giving me three stacks of Gushing Wounds. Again, we used the combination of Blood Mirror and Swarming Shadows to quickly kill the rogue, so that he would not become mind-controlled. At this point, the rogue stayed dead.

After a third minute, I cast my third Vampiric Bite, granting me the fourth and final stack of Gushing Wounds, which then promptly vanished from my debuffs bar, and I recieved Blood-Quenched in my buff bar, with a 6-minute timer. At this point, we no longer needed to kill the mage, as I knew that the boss would die within the next minute, and the mage would not become mind-controlled.

Assuming that everything has gone correctly, congratulations! You have completed Blood Infusion! Return to Highlord Darion Mograine to turn in your quest, and begin on Frost Infusion, which is incredibly easy.

Good luck!

This is what i did to solo this with not much trouble at all.
1. Disabled all my addons, i just renamed my addon folder, you can just change it back after.
2. Invited 3 of my alts to the same party as my main with [item=49888]
3. Cleared all the way to [npc=37955] left my main in the center of the room
4. Logged in to my my 3 alts 1 by 1 and logged them out in the center of the room
5. Logged back on my main, taunted the boss and did 1 auto attack (not sure if that matters)
6. Right after that auto attack i hit alt+f4
7. Started the game again and logged in to alt No1
8. As soon as i got logged in on alt No1 i hit alt+f4
9. Logged back on my main, had to wait to get the buff so i could bite, did the bite and hit alt+f4 right after
10. Logged alt No2, alt+f4 as soon as i got logget in
11. Logged back on my main, had to wait again for the buff to bite, alt+f4
12. Logged alt No3, alt+f4
13. Back to my main, bite and killed the boss.
14. Profit

I tested this a couple of times with my addons, but i could not do it, got killed.
With all my addons disabled it felt like i had all the time in the world, had to wait for the buff instead of being killed.
It took me many years to finish this one, but now when the 8.3 patch is on the horison i wanted to finish it.
I hope this can help someone, because i have tested it before with the help of videos and guides but couldent manage to get it done.