MLB, union float playing all games in empty stadiums in Arizona: report

[Ms. Toad]

50. It depends on the surface.

I don't know about baseballs, specifically - but in Ohio, after it was clear that the general public did not understand the 6' rule, Dr. Acton and Gov. DeWine expressly called out sports that share equipment (like playing pick-up basketball games and using shared playground equipment as troublesome, becuase the virus does live on many surfaces 3-5 days. You touch the virus, then touch your face, and you risk infection.

Here are a couple of examples from one of a number of substantially similar document. I didn't find a period of time for leather:

Wood
Examples: furniture, decking
4 days

Ceramics
Examples: dishes, pottery, mugs
5 days

AS to whether I'm dumping bleach on my Food or mail

Coronavirus doesn't seem to spread through exposure to food. Still, it's a good idea to wash fruits and vegetables under running water before you eat them. Scrub them with a brush or your hands to remove any germs that might be on their surface. Wash your hands after you visit the supermarket. If you have a weakened immune system, you might want to buy frozen or canned produce.

Paper
The length of time varies. Some strains of coronavirus live for only a few minutes on paper, while others live for up to 5 days.

https://www.webmd.com/lung/how-long-covid-19-lives-on-surfaces

So yes, it is one of the ways the virus is transmitted.