Why would there be any more need for weapons and ammo? If anything, the streets will be safer as sick people stay indoors and other people decide to hole up at home until the problem passes.
What about people who run out of food and live more on the "edge" of society? Might they not disregard health risks in order to get what they can from the "haves"?
I would have discounted that as paranoid before Katrina, but now I have seen how fast things can really break down. It's not an analagous situation, but I've learned that the social veneer is very thin indeed.
"Why would there be any more need for weapons and ammo? If anything, the streets will be safer as sick people stay indoors and other people decide to hole up at home until the problem passes."
Nope, sorry you are 100% wrong there. In the event of such a problem there will be people who will not have prepared. They won't have food, water or transportation. They might decide to take what they want starting with transportation, when they want it.
Self-defense prep is always required.
When panic starts, the lunatics go even more crazy. Home invasions will go up. Rioters and looters could destroy/empty the store shelves.
It is smart to be armed at all times. Common sense says that people will be at more risk if panic sets in and the crazies go wild.