Yes we have a New Challenge on the side mission Patient Zero
I don’t know how you plan to achieve but I did.
Began by helicopter landing, headed towards where the 2 doctors go inside but I used the ledge right of that door and pole climb down and to the left of pole is a window into bathroom. Wait for the 2 doc to leave and you can go in and then knock out doc with cage and take him out.
As you take his suit the doc he will become infected snap his neck too.
Exit the same way you enter. Back outside and enter where the 3 guards are waiting by the helicopter note the chopper isn’t present. Once inside go down stairs use a coin or screwdriver to remove the guard , guarding the antidote. Then enter where the 2 doctors are chatting from the main mission but there’s only 1 doctor, remove him and put in closet.
Then lie down in bed while infected, then get up and get antidote. You can be in the hazmat suit while lying down on bed. You can also shoot camera console
Then after antidote go upstairs take out last target. You can lure him out but note 1 doctor from the hallway does loop there, pacify him before he sees the last target killed.
The lying on a table/bed thing had me frustrated. But maybe because I was trying to do it on the one closest to where Agent Smith is in the normal mission. It kept saying “Too Suspicious” and that had me thinking I had to (infect and) kill more people than I probably needed to.
This was a bit of a show… Sorta forced to play it to get something and not just a casual playthrough for… fun? I don’t think this mission was EVER fun.
Last time I’ve tried SA this level, it was back in H2 and I used the electric phone to quickly kill the nurse that violates quarantine and begins the spread. This time I’ve decided to do it full SASO with zero NPC infections and no silly phones.
Started with a Sieker, crowbar (but any stick will do for this route) and keycard scramblers. Beginning was similar to OP: go up, wait for doctors to pass, climb down into the bathroom, lure the doctor with Cage into the nearby room and knock him out, catch Cage and snap his neck before he can enter the corridor.
From there I hid both bodies in a nearby closet and waited for an opportunity to lure the one guy standing in the corridor to the bathroom stall to knock him out too, which gave a clear path to the stairway that connects to morgue’s incinerator room. Siekered the guard in front of stem cell storage to make him walk away and not catch the infection, got onto the nearby bed to trigger the unlock, then continued with getting the antidote.
Returned to the action through the same stairway and slipped into the room with surgery robot controls. From there it was just a matter of throwing the crowbar to lure out of one the doctors, knocking him out and hiding him, then repeating that with Klaus but with a necksnap this time.
Escape was probably the most stressful part, but turned out smoothly. I made my way back to the morgue, dumped almost everyone there into closets to make sure noone could compromise me at this point, went to the garage and then ran towards the snow scooter.
Also props for IO for unlocking PZ outfit choice. Polar Survival Suit fits this mission very well.
I took out the nurse first and foremost and then took out sick guy (getting infected first). I went down to the morgue, lay on the table, and got to the cure. Then I went back upstairs and changed into a hazmat suit to take out the doctor. From there it was simple enough to get to an exit and end the mission.
show… Sorta forced to play it to get something and not just a casual playthrough for… fun? 
I don’t think this mission was EVER fun. 
