Cooperative Extension Service Communications and Technology Department 3354 1000 E. University Ave. Laramie, WY 82071 (307) 766-2540 • fax (307) 766-3998 • www.uwyo.edu

 

For Immediate Release

 

Contact: Robert Waggener, Editor

Phone: (307) 766-3571

E-mail: robertw@uwyo.edu

 

Date: March 21, 2007

 

Dog owners not cleaning up after pets put other dogs, humans at risk, according to UW study

            Dog owners not cleaning up after their pets are putting other dogs and unborn puppies – even humans – at risk for parasitic worms and protozoa, according to research by the University of Wyoming’s College of Agriculture.

            William Jolley, an associate professor in the Department of Veterinary Sciences, and two students last fall and this winter examined nearly 250 fecal samples collected from Laramie parks and walking paths.

            Sixteen of the samples left by dogs contained parasitic worm eggs or the cysts of Isospora, a parasitic protozoan, according to a three-page article written by Jolley titled “Unwelcome Worms.”

            Assisting him in the research were Brian Hardy of Cheyenne, a senior majoring in microbiology, and Alexandra Keeler of Douglas, a senior majoring in molecular and microbiology.

            Jolley said 12 of the samples had roundworms and four had Isospora.

            “Of the organisms found, the ascarid roundworms pose the highest risk to dogs, unborn puppies and possibly even humans,” Jolley said. Ten of the samples were infected with ascarids, the largest of the three roundworm species found in the dog piles.

            “The ascarid is unique by its ability to infect developing puppies in the uterus of a dog with a latent infection of larvae in her tissues,” Jolley said. “Unborn puppies can suffer serious damage by the migration of the larvae through their bodies from the tissues of a pregnant female.”

            By the time the puppies are two or three months old, Jolley added, they can have adult worms in their tiny intestines. A severe infection can cause intestinal blockage, which can be fatal if left untreated.

            Jolley said fecal matter infected with roundworm eggs also poses dangers to children playing in a park or other areas frequented by dogs if they accidentally ingest such matter.

            “A small infection with the ascarids may be unnoticeable, but a large one may cause serious damage to the eyes, central nervous system and other organs – or even death,” he said.

            Humans are even more susceptible to infection by hookworms in fecal matter, but the damage is limited to the skin, not internal organs, Jolley said. One of the samples contained hookworms, another roundworm species of dogs.

            “The hookworm invades any host whose skin comes into contact with a larva in soil, grass or carpet,” he noted. “The burrows in the human skin become inflamed, itchy and sore, and the trail of the worms can be traced by the lines they leave during their migration.”

            Jolley said he knows of several UW students and Laramie residents who have had this skin affliction.

            The third roundworm found was the whipworm, which was in one sample.

            Though there is a chance a person could become infected with worms or protozoa, said Jolley, the most likely victim will be a dog that ingests infected feces either intentionally or accidentally.

            “To help prevent this from happening, pet owners are encouraged to clean up after their animals,” Jolley said.

            This is important, he says, because the eggs, particularly those of the ascarids, can survive for many months, even during freezing temperatures.

            He adds that dog owners should have recently acquired adult dogs and puppies tested for worms, and infected animals should be treated.

            Also, he said, if a dog is taken to a warmer climate, which would likely have higher parasite prevalence, it should be tested within three or four months of returning home.

            Samples were collected in Laramie from Kiwanis, LaBonte, Old West, Optimist, Undine and Washington parks, walking paths adjacent to the Laramie River and sidewalks along McCue Street.

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