What is Parvo and is your puppy at risk?

Ruth Bader Ginsburg overseeing content creation

What is canine parvovirus (parvo)?

Canine parvovirus (parvo) is a type of virus that infects dogs, cats, and other canines. Infected animals may show no symptoms at all, but the virus is best known for causing diarrhea, intestinal bleeding, and sepsis. If left untreated, canine parvovirus can be lethal.

How do puppies get parvo?

Puppies can get parvo by swallowing dirt or feces that contain the virus. This is easy to do when they come into contact with an infected dog — especially because dogs tend to meet each other by sniffing their rear ends [2].

Ruth and her best friend, rolling around in the backyard

Is parvo in your backyard?

Unfortunately, the answer is: Maybe.

A man narrowly avoids attack from Ruth on an SF beach

Urban wildlife and parvo

As mentioned earlier, canine parvovirus can infect more than dogs. Raccoons, coyotes, wolves, and foxes have all been found to carry canine parvoviruses, sometimes without symptoms [4–11].

What are the symptoms of parvo?

Parvo wreaks havoc on dogs’ digestive and immune systems. This causes a number of related symptoms that include [1,2]:

  • Sluggishness
  • Vomiting
  • Loss of appetite
  • Inability to keep water down
  • Particularly foul smelling, mustard yellow diarrhea (possibly with blood in it)
  • Fever
  • Tenderness around the dog’s stomach

Preventing parvo

Fortunately, there are steps you can take to protect your dog.

Ruth in her comfortable swaddle

Have fun and be safe

In those first few months, have fun with your dog and remember to laugh, even when they’re frustrating. Fear of parvo shouldn’t paralyze you, but you should take it seriously and whenever possible, er on the side of caution. (And please, pick up your dog’s poop—it’s hard to know if they’re carrying any viruses that can spread through feces; picking up the poo will help protect other dogs and wildlife).


(There were many more not listed here, but these should get you the information you’re looking for.)

  1. Horecka, Kevin et al. “A Decade of Treatment of Canine Parvovirus in an Animal Shelter: A Retrospective Study.” Animals : an open access journal from MDPI vol. 10,6 939. 29 May. 2020, doi:10.3390/ani10060939
  2. Nandi, S, and Manoj Kumar. “Canine parvovirus: current perspective.” Indian journal of virology : an official organ of Indian Virological Society vol. 21,1 (2010): 31–44. doi:10.1007/s13337–010–0007-y
  3. EJ;, Gordon JC;Angrick. “Canine Parvovirus: Environmental Effects on Infectivity.” American Journal of Veterinary Research, U.S. National Library of Medicine, pubmed.ncbi.nlm.nih.gov/3017161/. — NOTE: This paper is unavailable in electronic copy. I had to base my understanding of this paper on the abstract.
  4. Muneer, Mohammad A., et al. “Detection of Parvoviruses in Wolf Feces by Electron Microscopy.” Journal of Wildlife Diseases, vol. 24, no. 1, 1988, pp. 170–172., doi:10.7589/0090–3558–24.1.170.
  5. Allison, Andrew B et al. “Frequent cross-species transmission of parvoviruses among diverse carnivore hosts.” Journal of virology vol. 87,4 (2013): 2342–7. doi:10.1128/JVI.02428–12
  6. Kelman, Mark et al. “Phylogenetic and Geospatial Evidence of Canine Parvovirus Transmission between Wild Dogs and Domestic Dogs at the Urban Fringe in Australia.” Viruses vol. 12,6 663. 19 Jun. 2020, doi:10.3390/v12060663
  7. Calatayud, Olga et al. “Carnivore Parvovirus Ecology in the Serengeti Ecosystem: Vaccine Strains Circulating and New Host Species Identified.” Journal of virology vol. 93,13 e02220–18. 14 Jun. 2019, doi:10.1128/JVI.02220–18
  8. Duarte, Margarida D et al. “Snapshot of viral infections in wild carnivores reveals ubiquity of parvovirus and susceptibility of Egyptian mongoose to feline panleukopenia virus.” PloS one vol. 8,3 (2013): e59399. doi:10.1371/journal.pone.0059399
  9. Mech, L. David, et al. “DEMOGRAPHIC EFFECTS OF CANINE PARVOVIRUS ON A FREE-RANGING WOLF POPULATION OVER 30 YEARS.” Journal of Wildlife Diseases, vol. 44, no. 4, 2008, pp. 824–836., doi:10.7589/0090–3558–44.4.824.
  10. Voorhees, Ian E H et al. “Limited Intrahost Diversity and Background Evolution Accompany 40 Years of Canine Parvovirus Host Adaptation and Spread.” Journal of virology vol. 94,1 e01162–19. 12 Dec. 2019, doi:10.1128/JVI.01162–19
  11. Spera, Caroline Giuseppa, et al. “Canine Parvovirus 2b in Fecal Samples of Asymptomatic Free-Living South American Coatis (Nasua Nasua, Linnaeus, 1766).” Brazilian Journal of Microbiology, vol. 51, no. 3, 2020, pp. 1399–1403., doi:10.1007/s42770–020–00293–2.
  12. Sykes, Jane E. Canine and Feline Infectious Diseases. Elsevier/Saunders, 2014.
  13. Day, M J et al. “WSAVA Guidelines for the vaccination of dogs and cats.” The Journal of small animal practice vol. 57,1 (2016): E1-E45. doi:10.1111/jsap.2_12431
  14. Wilson, Stephen, et al. “Influence of Maternally-Derived Antibodies in 6-Week Old Dogs for the Efficacy of a New Vaccine to Protect Dogs against Virulent Challenge with Canine Distemper Virus, Adenovirus or Parvovirus.” Trials in Vaccinology, vol. 3, 2014, pp. 107–113., doi:10.1016/j.trivac.2014.06.001.



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Stephen Riffle, Ph.D.

Stephen Riffle, Ph.D.

Stephen is a professional science writer covering microbiology, evolution, and anything else he finds interesting.