I live in an apartment complex with a ton of dogs, and there are no real "dog-free" areas where I can take my 10-week old puppy to do his business and play outside. How dangerous is it for him to walk around in the grass outside and do his business? I got him 2 weeks ago and everything has been going great, but I'm a bit paranoid about him catching parvo or other diseases. I just don't know of any totally dog-free areas to take him.