Back to Stories & News

June 1, 2017 – Summertime is just around the corner and that means time in the water for us and our water-loving dogs. While swimming and playing in the water is great exercise for our pets – and an easy way to cool down on a hot summer’s day – owners need to be aware of water-borne diseases their pet may be exposed to, and what to do about it. Water environments, particularly natural bodies of water, provide a welcoming home for diseases that can be passed from one animal to another. Some of these diseases are easily treatable and pose little threat, while others can be devastating. Being a knowledgeable owner can help you protect your pet this summer.

What’s lurking in the water?

Water-borne disease are tricky for owners because most of the time the danger is not obvious. Here are some of the most common water-borne diseases in dogs, along with signs you might see, treatments and possible outcomes from infection.

Leptospirosis – treatable but can be fatal in severe cases

  • Leptospirosis is caused by bacteria (Leptospira spp.) that have world-wide distribution and can infect any mammal.
  • Dogs contract the disease through contact with infected urine or water, but not all infected dogs become ill.
  • The most common signs reported in dogs are fever, anorexia, vomiting and diarrhea, but signs can vary. Kidney and liver damage have been reported in some dogs.
  • Antibiotic therapy is needed to clear the organism, and supportive care and hospitalization is required in the most severe cases.
  • Prognosis depends on the severity of organ damage and the presence (or absence) of complications. Mortality rates are 20 percent, although some experts report mortality rates as high as 70 percent in the most severely affected individuals.
  • Vaccination can help prevent infection but may not offer complete protection.

Giardiasis – treatable with good long-term outcomes

  • Giardiasis is caused by protozoa (Giardia spp.) with a wide geographic distribution.
  • Diarrhea is the most common clinical sign, but many healthy dogs have giardia organisms in their stools.
  • De-wormers such as fenbendazol, or antibiotic therapy with metronidazole, are used to treat symptomatic dogs, and long-term prognosis is very good.

Pythiosis – rare, but serious and often fatal

  • Pythiosis is caused by a type of fungus (Pythium insidiosum) that causes very serious and often fatal infections of the skin or intestinal tract.
  • Pythiosis most often is seen in the Gulf Coast states, but it has been recognized in several Northern, Midwestern and Western states.
  • Clinical signs include ulcerated, non-healing skin lesions, weight loss, vomiting, diarrhea and bloody stools.
  • Surgery to remove lesions on the skin and in the bowel is the treatment of choice for this disease, but many times the lesions are too extensive to remove.
  • Oral anti-fungal drugs can be tried in cases where surgery is impossible, but rarely are successful at curing the disease. Fortunately, this infection is rare in the United States.

Protothecosis – in immunosuppressed dogs can be fatal

  • Protothecosis is caused by an algae (Prototheca spp.) found in warm, humid regions such as the Gulf Coast states.
  • Although many dogs come in contact with this organism, illnesses are rare and often associated with immunosuppression.
  • The organism can cause skin lesions as well as central nervous system signs (such as seizures, blindness and incoordination) and diarrhea, vomiting and weight loss if the large intestine is involved.
  • Treatment with anti-fungal agents has been effective; most dogs with clinical infection succumb to the disease.

Expanding areas of infection – what should I know before I go?

Many water-borne diseases previously were confined to certain defined areas of the United States. But with climate change, and an increasingly mobile society, infectious agents are moving into new territories. Your veterinarian can be a good source of information on the diseases prevalent in your area. The Centers for Disease Control also has information on diseases affecting your pet.

What can I do to protect my dog, but still let them have fun in the water?

Know the risks for your area, and protect your pet (and yourself) by following a few simple rules when it comes to reducing the chances of contracting a water-borne disease.

  • Pay attention to the signs posted around water areas. If signs say an area is not safe for swimming or fishing, it’s probably not safe for your dog, either. Err on the side of caution.
  • Don’t let you pet play in or drink water that has a rotting egg smell or dead fish floating in it. It is likely contaminated with a pathogen or pollutant.
  • Crystal clear water like that found in mountain streams does not equal safe. When hiking with your dog, it’s best to bring his or her own water supply, or carry with you a water purification system. Beaver dams are a good indication that water may be contaminated with giardia.
  • Don’t let your dog play in bodies of water than contain wastewater from treatment plants.

What is Morris Animal Foundation doing to combat water-borne diseases?

Morris Animal Foundation has funded several studies looking at water-borne diseases, as well as other disease-causing organisms. Infectious diseases of all types have been a major funding focus since 1956, when we funded our first study on leptospirosis in dogs. We’ve continued that commitment for nearly 70 years, and are a leader in the study of infectious diseases of all animal species. The Golden Retriever Lifetime Study is an opportunity for the Foundation to look at infectious diseases in a closely monitored cohort representing dogs across the country. The study will provide important details on infections with a variety of organisms, and might shed light on how infection can influence the development of other diseases. For example, XXXX dogs have been diagnosed with giardia infections, and over time we might be able to show how that plays out as a risk factor for other health concerns. Check out our current and past studies on infectious disease in dogs, as well as our other research projects.

Prevention is best – then go have some fun!

As a dog owner, many water-borne diseases are scary to contemplate, but the good news is that many are treatable, and others are rare. You also have some control over the water your pet is exposed to, and shouldn’t let your dog drink from or swim in water that isn’t safe for people. Physically engaging activities such as swimming and hiking are great for our pets, and for you. Understanding and preparing for hidden dangers in the water when you venture out this summer can help keep your dogs happy and healthy and swimming the summer away.