Dog faeces may contain parvovirus, whipworms, hookworms, roundworms, threadworms, campylobacteriosis, giardia, and coccidia. If left unattended, these parasites will contaminate the water, soil, and can even cause infection in both pets and humans (especially children). The microscopic Hookworm larvae can be passed to another pet or person directly through the skin or by accidental ingestion as can other bacteria.
Pet faeces can contaminate nearby ponds, lakes, rivers and drinking water. When faeces is allowed to remain on the soil for long periods, rainstorms will begin to dilute and break apart the faeces and slowly spread the bacteria on other contaminants into local water sources. If your yard happens to hold water for extended periods of time, the problem may be amplified.
To avoid potential infection, dog faeces should be removed from the yard every 1 - 7 days, depending on the size of the dog and number of dogs in the household. Larger dogs will need more frequent cleanup, as will households with more than 1 dog. A family with one Pomeranian will have a much lower environmental impact than the family with 2 Great Danes.
Ok, I have said the word faeces far too many times on one page. If you are too busy to scoop, or the thought of it just makes you gag...