The Last of Us: source of new infected?

Just finished the Last of Us. Yes, I know it’s an old game, but folks are still discussing it, viz. Played Remastered version on PS4, totally blew me away.

Anyway, I couldn’t help but wonder if the game designers had thought through the logic of where new infected keep coming from 20 years after the initial outbreak? Maybe it’s an oversimplification, but if they really closed off a quarantine zone, how long would it take for the infected outside to die of hunger, exposure, cannibalism, etc? Maybe the spores have a very long life?

Another one: where’s food coming from? There’s no evidence of traditional or hydroponic farming in all of the terrain that’s covered. Seems like any preserved food would have long been consumed, even by the reduced population.

I know it’s just a game, but it was so well done that these couple of items are nagging me. Help me accept an explanation that’s at least marginally plausible.

Well no Zombie game or tv series or movie stands up to close scrutiny or matches with the laws of thermodynamics. They never explain where zombies get energy from and if its from eating each other then they should all die out pretty rapidly.

Plus the US armed forces would easily deal with any real zombie outbreak. An unintelligent foe that is incapable of communication or making plans? And that doesn’t use weapons or seek cover when advancing? They’d be slaughtered within a week. Napalm and mini-guns or just good old .50 cal machine guns would easily deal with them.

So put those objections aside, my take on the back story was this. First, yes I got the impression that the spores could lie dormant essentially forever, so people could get infected even after 20 years if they came across a patch of spores. Second, people would leave the quarantine areas to go scavenging, for metal, weapons, to go hunting, etc etc. Possibly part of the time with official permission and some of the time without using hidden tunnels etc.

I guess also they would have to have other areas that we didn’t see where they grow crops hydroponically. Also from what I remember the cordyceps fungus did not effect animals and the infected didn’t seem to pay attention to them. So given the 20 years of confined human activity animal populations would have grown dramatically and so well armed parties could leave the quarantine area to both hunt game and scavenge for berries, fruits etc.