The Importance of Picking Up After Your Pet

Ahh…Spring! For much of North America, the record snowfall, rain and flooding have left many of us feeling battle-worn. So, while spring brings renewal and revitalization, many will be facing the specter of excessive pet waste as the winter grounds thaw around us and even in our backyards!

No matter what the conditions are outside – snow, rain or sunshine – we should always pick up your pet’s waste [yes, even for cats]. It’s not only neighborly, it’s also for the health of you and your animal companions.


A group of researchers looked into the abundance of airborne bacteria during summer and winter months in the Great Lakes Region. They found predictable sources and levels of bacteria from leaves and soil. Their air sampling also revealed that in some areas the dominating airborne bacteria was from dog feces. The percentage of bacteria from dog feces compared to the other sources was around 10% in the summer and up to 25-70% in the winter. How could they surmise dog feces was the source? Presumably, because, the bacteria found – Bacteroidetes, Clostridiales and Fusobacteria – are common inhabitants of the mammalian gut, although this includes that of cats and other mammals including humans.


The United States Environmental Protection Agency (EPA) and state agencies have launched major campaigns to motivate people to pick up after their pets because of stormwater runoff or pets defecating near watersheds…and with good reason.

  • Seattle’s Pipers Creek – Seattle’s Drainage and Wastewater Utility conducted a study in 1992 to track the source of fecal coliform (bacteria) in Pipers Creek. The study examined ribonucleic acids (RNA) found in fecal coliform from creek samples and compared it to fecal coliform from various sources such as feces of humans, dogs, birds, and small mammals. This study concluded that the fecal coliform found in Pipers Creek was not of human origin. It came from a number of sources. The primary sources were cat and dog wastes of the 40% that could be traced.
  • Little Soos Creek – Another study performed in 1998 also in the Washington area found that nearly 20% of the bacteria isolates that could be matched with host animals were matched with dogs.

These examples may involve the Washington state area, but the persistence of pet waste in waterways affects people, plants, food, marine, freshwater and land animals around the world.

First and foremost, think about the numerous food recalls due to E. coli outbreaks that originate from water contaminated with fecal waste.

Plus, pet and other mammalian waste could be seeping into our drinking water.

While this waste can contribute the better known E. coli and Giardia spp. to water along with many other microbes it also adds to cyanobacterial blooms (also know as blue-green algae blooms). These algae live in all types of water, and depend upon fecal nutrients to grow. As they replicate, the oxygen supply in the water becomes depleted which affects both freshwater and marine life.

As responsible pet owners, let’s not contribute to these recalls and help sustain life.


Let’s suppose that you or your neighbor only pick up pet waste weekly. That’s how long it takes for roundworm parasite eggs to become infectious in aging animal feces. Then, they persist. Roundworm eggs typically live for years in contaminated soil because they, and whipworm eggs, can survive at freezing temperatures. By contrast, hookworm eggs are killed by freezing temperatures.

Of course, you would not allow your pet companions to defecate in or around a vegetable garden as this could lead to intestinal bacterial infections for your family, other humans or pets that eat the contaminated food.

Immediate Bacterial Infections

Aside from the environmental concerns, we need to consider the immediate health implications from fecal waste. For instance, giardiasis is an intestinal infection caused by Giardia spp. parasite. The oocysts are immediately infectious upon defecation just like Campylobacter and Salmonella bacteria. While atmosphere and environmental conditions affect each bacterium or parasite differently, we know that Giardia oocysts can survive more than two months in cool water, and about one month at room temperature, can withstand one freeze-thaw cycle, and are sensitive to desiccation, sunlight, and freezing. Remember that this parasite can be present in the feces of all mammals including humans.

Staphylococcus aureus (MRSA), and Yersinia bacteria can also be spread by fecal waste as well.


Canine parvovirus can also be spread by infected dog feces. W. Jean Dodds and Hemopet highly recommend that dogs be vaccinated against parvovirus at 9-10 weeks, 14-15 weeks, and 18 weeks of age. Please note that Feline panleukopenia virus, an important viral infection of all species of the cat family, is also a parvovirus. Vaccination of kittens for this common virus is also important.

How to Pick Up

The simplest way is:

  1. Take a plastic bag
  2. Put your hand in it
  3. Pick up the waste
  4. Invert the bag
  5. Tie it off
  6. Throw it in the trash. If you want, you can also flush the pet waste down the toilet.

A compostable bag is a more earth-friendly bag option, since it is typically made of corn instead of oil. This does not mean you should compost it though, as composting pet waste can be tricky and should be done judiciously. In fact, many municipal composting facilities do not allow pet waste. We would advise only to compost pet waste if your city or municipality has a designated pet waste composting facility. You can still throw away the compostable bag in the garbage.

With whatever method you choose, please wash your hands afterwards with warm soapy water.

It’s Not Me, But My Neighbors…

If you pick up after your pet, but your neighbors don’t, you could consider starting a pick-up campaign in your area. Several resources and marketing materials are available on the web from the EPA, and individual states and municipalities.


Beeler, Emily, and Meredith May. “The Link Between Animal Feces and Zoonotic Disease”. Los Angeles County Public Health,

Bowers, Robert, et al. “Sources of Bacteria in Outdoor Air across Cities in the Midwestern United States.” Applied and Environmental Microbiology, vol. 77, no. 18, Sept. 2011, pp. 6350–6356, doi:10.1128/AEM.05498-11.

Bowman, Dwight. “Year-round heartworm control from Maine to Cuba (Proceedings)”. 260 Veterinary Calendar, 1 April 2009,

Cinquepalmi, Vittoria et al. “Environmental contamination by dog’s faeces: a public health problem?”. International Journal of Environmental Research and Public Health, vol. 10, 1 72-84. 24 Dec. 2012, doi:10.3390/ijerph10010072.

Deviaene, Meagan, and Joanna Harrison. “City of Auburn Pet Waste and Water Quality”. University of Washington Department of Environmental and Occupational Health Services, 2016,

Dodds, Jean. “2016 Dodds Vaccination Protocol for Dogs”. Pet Health Resources, Tumblr, 18 July 2016,

“Woonasquatucket River Fecal Coliform Bacteria and Dissolved Metals Total Maximum Daily Loads”. Rhode Island Department of Environmental Management Office of Water Resources, Apr. 2007,

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