A woman recently walked into her veterinarian’s office complaining that she had seen worms in her dog’s stool. When she later brought in a sample it was confirmed that her dog did indeed have worms. She asked about treatment, the safety of her family and prevention. She asked why, when she had brought up parasite prevention before to her local Tucson veterinarian, he had told her that Tucson was too dry for parasites to pose a risk to her pets or family. As the diagnosis provided clearly indicated that her veterinarian was wrong, the question arose, do Tucson area dogs need to be on parasite prevention?
Tucson is very dry, often receiving fewer than 15 inches of rain a year. Some intestinal parasite eggs cannot tolerate that level of aridity. However, Kentucky Bluegrass requires upwards of 110” of water a year, while Bermuda grass, the most common grass seen in Tucson area parks and golf courses requires about the same.
If your dog commonly walks on golf courses, in public parks or in dog parks, your dog is at increased risk of internal parasites because the eggs shed in the feces do not dry out under the humid conditions produced in these environments.
There are several parasites that your dog can come into contact with. The scary ones for human health are roundworms, hook worms and whip worms. All of these can be passed from bitch to pup and due to this the Companion Animal Parasite Counsel and the CDC recommend routine deworming of all puppies and kittens as well as several fecal exams.
The reason for several fecal exams is that finding no worm eggs does not mean that there are no parasites present, it simply means that they are too immature for reproduction or that they are in between breeding cycles. Most hospitals will want to perform two fecal exams at minimum.
Deworming is also a necessary aspect of puppy parasite control. Most hospitals will routinely deworm young pups and kittens. The number of dewormings varies from veterinarian to veterinarian; the CDC recommends deworming every two weeks through week 8-12 and then again at 6 months. Since puppies this young are not routinely seen by a veterinarian, your own veterinarian may have a different protocol. What is important is that puppies be dewormed regularly.
Veterinarians do this two-tier approach because parasites are not just dangerous to your pets, but to your family. Research indicates that 7.3% of US children have contracted roundworms. Roundworms in humans tend to migrate below the skin and into eyes, causing blindness.
After routine deworming and several fecal exams that produce no evidence of parasites, dogs should be placed on a monthly preventative such as Heartgard Plus, which is effective against heartworms, roundworms and hookworms.
Less dangerous to your family, but still a common problem, especially here in Tucson, is giardia. Giardia is a water borne single celled organism that can cause “Montezuma’s Revenge” in people. Dogs can be silent carriers, exhibiting no outward signs of illness. At this time there is no effective prevention against giardia. Dogs can contract giardia through fecal contamination of water dishes (usually by birds). Other common sources are puddles, stock ponds, streams, lakes and water fountains. This is the most common parasite that affects humans in the US.
Tapeworms are the most commonly seen worms in adult dogs in the Tucson area. Adult dogs can acquire tapeworms through ingestion of other animals (rabbits, mice, rats and even insects) as well as fleas. In Tucson, rodent ingestion is the most common cause. In rare instances humans can acquire a relatively rare species of tapeworm from raw meat or from an infected pet. In humans the worm can cause cysts in the liver, lungs and brain. Virbac’s Iverhart Max can prevent tapeworms as well as roundworms, hookworms and heartworms.
The last common intestinal parasite is called coccidia and it is a single-celled organism. Most often these are found in puppies and are asymptomatic (meaning that there are no symptoms). Because it can cause serious issues in dogs with other illnesses it is treated even when found in otherwise healthy dogs.
Are Tucson dogs at as much risk as dogs living in wetter locations? No, but to say that there is no risk, or that the risk is marginal does your family and your pets a disservice. Most intestinal parasites are relatively easy to eliminate once your pet has contracted them, however, as in most cases prevention is a far better road than treatment. Some of these worms cannot be reasonably prevented, but for the other ones, the ones that are the most dangerous to your pet and family there is a safe and effective prevention: monthly heartworm prevention.