I've planted about 5 sugar snap peas in different pots away from each other. One of them developed brown spots, yellowing leaves and is on its way to dying. The others are thriving. A little yellowing on the bottom leaves, but otherwise, lively and producing peas.

Several questions:

-Is it a virus?
-Can I eat the peas that it has been able to produce?
-Will it spread to other pots? How does the virus spread?
-Can I replant dill in the same pot/soil? (low on soil right now, so would like to just yank out the old and put some dill in there. Or is the virus universal to all plants and I would have to bleach the pot?

Thank you!