Can't complete Prelude to a Plague

[Missa]

I am on a quest about the whole town having the plague and I am on the last step - add the potent anti-virus to the well, which my physician did, but the option didn't clear when I did it. It told me I added the medicine in the upper right corner, there is no more anti-virus in my inventory and I can't make more so I'm not sure if I'm missing something (according to the Prima guide this is the last step of the quest) or if it is a bug and I should quit and restart? Has this happened to anyone?

[Lilygirl]

I have found that most times, after the last step has been completed in quest, the game takes a couple Sim-minutes to acknowledge it and bring up the completion screen. If nothing pops up just to the right of your hero's picture (where the quest tasks are) I would advise to give it a few Sim-minutes. I haven't completed this particular quest so if anyone has, please feel free to step in.

[Ricalynn]

If I finish something I tend to just move on and about halfway back home to sleep, the quest completes.

[Simmerqueen]

You do need to make two portions of the anti-virus even though you only do the 'add to well' option once.  Did your physician have two in inventory when you went to the well?

[Missa]

I made two potions and the quest had me give the first one to one of the sick patients, then it had me add the second one to the well. I have been through a whole new day after adding it to the well. I even tried to make some more potion, but it won't let me. I saved my game under another name so that I could go back and do the quest over.

[Simmerqueen]

That's weird, because on mine it didn't have me give any to a sick patient at that time when I was doing the well.  The sick patient anti-virus had been made and given quite a while before the two that I had to make before I went to the well.

[thadine]

When you go to add the potion to the well, you have to pick the option "Add Antidote" and NOT the option that says "Add Medicine" (or something like that, I forget the exact wording). I made that mistake and couldn't finish the quest. I had to go back to a saved game and redo the quest.

[Missa]

I think I choose "Add Antidote" but I can't remember  I will need to load my game before that quest and try it again. I started a new game since I hadn't realized that I shouldn't rush through the quests so I am focusing more on making sure I finish each quest at platinum and level up each hero as much as possible before the quest is over. Thanks for the help!