What happens if two upgrades tie

It was a one-time item given out by the developers to beta testers. Using it sets your AP to 30/6. It doesn't count as a drug for the purposes of the "Clean" status (i.e. you're still clean after using it).

It's marked a "Professional tool" and therefore can't be dropped. If a person carrying one does manage to drop it somehow (i.e. by dying) it can't be picked up again by anyone else.

When you're infected, you have a 50% chance of dying overnight, every night. You will not, however, infect fellow citizens. The infection stays local to you and you're not going to accidentally decimate your town. The worst that can happen is you die overnight and they either have to water your body down or drag it out into the wasteland.

Do not sacrifice yourself out of fear of this; I've managed to survive two nights in a row in spite of being infected and I can confirm you're more valuable to your town if you manage to stay alive.

There's a drug called the Paracetoid 7g which will cure your infection; in order to get it you're going to have to mix pharmaceutical products together and hope you're lucky.

As a side note, if you get infected via wound, it's not enough just to take the drug; you need to bandage the wound or the infection will return the next day.