When you don't pick up dog waste you are essentially creating a smorgasbord for rats to feast on. If you live in a rural or spacious suburban area rats aren't as big of a worry, but if you reside in a major metro area leaving dog waste on sidewalks and streets can have real consequences. Rats can spread numerous diseases and any measure you can take to avoid them (like picking up your dog's waste!) is a good one. Rats are known to spread diseases and parasites like salmonellosis, trichinosis roundworms, murine typhus, rickettsia, melioidosis, pasteurellosis and brucellosis to humans and leptospirosis to both humans and dogs. By not picking up your dog's droppings you are inviting these disease carrying vermin to inhabit the areas where you take your dog for a walk and unwittingly inviting disease into your community. Although most major metro areas already have a strong rat presence, not picking up canine feces will only make rats congregate in your area. Although they are a lesser concern than rats, flies are also a factor if you don't clean up after you dog. It's no secret that flies are attracted to excrement, flies will swarm all over a fresh piece of waste looking to devour micro organisms. Flies can spread a lot of disease and they are constantly touching the filthiest surfaces. The flies go from waste, to other surfaces dragging with them all the bacteria they've touched. Although they might not seem as threatening as rats, they pose a very real risk if they are provided with enough waste.
If you don't already, save every plastic grocery bag that comes into your house. These bags are the perfect receptacle for doggy business and they are never in short supply. Keep the bags next to wherever you store your pupper's leash, that way when you leave your house for a walk you won't forget the bag and be forced to leave any pooch business on the sidewalk for an innocent by-passer to step in. It might not be the most glorious moment of your day when you use the plastic bag like a glove to pick up that doggy mess, but it is your duty as a pet owner and something you signed up for from the start.
If you believe in karma, or just enjoy being a good Samaritan, picking up your dog's mess is the right thing to do. Owning a dog is one of the most rewarding experiences you can have, as a pet owner you get so much joy and unconditional love from your pet, it's time you start unconditionally picking up their leavings. Once it's in the bag you can find your nearest trash, throw out the doggy business, clean off with some hand sanitizer and never think about it again.