Canine tapeworms are intestinal parasites that attached themselves to the intestinal wall with their hook-like mouths and may reach several inches in length by adulthood. Dogs become infected with tapeworms by eating fleas that are infected while licking or chewing themselves. Dogs can also become infected if they eat a rabbit or rodent that has tapeworm, although this method of contracting the parasite is much less common.
It's rare for humans to contract tapeworms but it can happen. More commonly, this occurs with children rather than adults. Children playing with pets or outside, such as in a sandbox, may accidentally swallow an infected flea. Tapeworms can not be passed between children or adults. Humans can only become infected with the parasite by ingesting infected fleas. The symptoms for humans are similar to those of dogs and include segments of tapeworm (resembling grains of rice) being passed in the feces and/or appearing stuck on the skin around the anal area.
The best way to prevent tapeworm in you and your pets is year around flea control.