Urban parks are a common destination for owners and their dogs. Parks encourage a broad scope of healthy physical activity, including dog-walking, and are areas of socialization for dogs and their owners. However, urban parks are also often confined areas where wildlife, dogs, and humans are sympatric, introducing the potential for disease transmission among domestic and wild animals. Among the most commonly found parasites are Giardia, Cryptosporidium (14.7%), and Cystoisospora (16.8%). Helminths include Capillaria, Eucoleu, Trichuris (whipworms), Toxascaris leonina, Toxacara canis, Taenia tapeworms, Diphyllobothrium tapeworm, and Uncinaria stenocephala (hookworms). Intact and young dogs are more susceptible to infection with any parasite and Giardia species, while the intensity of infection is positively associated with dogs visiting multiple parks coupled with a high frequency of park use and off-leash activity, and with being intact and young. About fifty percent of adult dogs visiting dog parks are infected with at least one parasite, while the rate of infection among young dogs is even higher (70%). Environmental contamination and undisposed dog feces positive for zoonotic and non-zoonotic gastrointestinal (GI) parasites have been reported in urban parks, suggesting parks as potential sources of GI infection for dogs, humans, and wildlife.
One of the biggest risks is the spread of infectious diseases. To minimize your dog's risk of getting sick, make sure all its vaccinations are current. "Dogs that are very sick do not usually feel well enough to run and play at a dog park," says Dr. Sheila McCullough, formerly a veterinarian at the University of Illinois Veterinary Teaching Hospital. "So serious infectious illnesses may not be a major concern. Common sense should tell a dog owner to keep a dog at home if it is coughing or vomiting or has diarrhea."
Another potential health hazard is injury from dog bites and fights. Serious injuries can be fatal. The best guard against this hazard is prevention. To prevent dangerous situations involving your dog, make sure your pet is well trained. If your dog does not come when called or has displayed inappropriate behavior around other dogs and people, then do not take your pet to a dog park.
Happy-go-lucky owners almost arrive to a dog park with a leashless dog. They come with the best of intentions, full of hope for a fun day and a promise of good times. Then, the dog sees a squirrel, a cat, or another dog... at best the good time is ruined by a chase; at worst a dog and/or person is hurt.
Another potential risk is dog fights. Your dog is attacked by another dog. You reach in, desperate to save your dog, and are bitten by another dog, who is clearly at fault for the vicious attack. It will be difficult to establish yourself as a victim and claim any medical expenses resulting from the incident, because your dog was off leash.
Most dog parks depend on dog owners to keep dog parks clean. Without a regular clean-up crew, parks can be very unhealthy. Dogs can contract a variety of diseases, including worms, from untreated, infected animals. Dog feces are often infected with at least one parasite: hookworms, Cryptosporidium species, Giardia, Toxascaris leonina, Cystoisospora, and Sarcocystis species. The soil of all the parks is often contaminated with hookworm eggs. Infection with internal parasites is positively associated with off-leash activity, park visitation frequency, and visiting more than one park.
The assumption has always been that only loving, caring dog owners invest time and effort to take their (well-cared-for) dogs to the park. Not so. Weigh the health risks; your own and your dog's; before spending too much time in the dog park. The dog park promises an hour of great fun, but the long-term ramifications of the dog park are often not what owners want. Dog parks teach dogs jump wildly on people, ignore the calls of their owners and, possibly, to fight. Dog trainers insist that the same kind of exercise and fun can be had by hiking/walking/jogging with your dog and going through the paces of dog obedience.