By Sandy Robins

Two diseases are becoming threats to dogs and, by extension, to humans. Leptospirosis, a bacterial infection, and Lyme disease, which can result from a single bite by an infected tick, are on the rise nationwide in urban, suburban, and rural areas.

These diseases, which can dangerously impact a dog’s health, have shared risk factors based on geography and lifestyle but both are preventable. If either of these diseases is prevalent in your community, it’s a good idea to talk to clients about them or include information on your website or in newsletters or emails. Here’s what you need to know to educate clients about them, including preventive measures.


Leptospirosis, sometimes called swamp fever, is caused by approximately 230 recognized species of Leptospira bacteria that enter a dog’s system via mucous membranes and then replicate in the bloodstream and move into the body’s tissues, primarily the liver and kidneys.

“The bacteria mainly settle in the liver and kidneys. Once there, they damage these organs, sometimes fatally. The death rate is one out of every five dogs diagnosed with this disease,” says Bonnie Bragdon, DVM, MS. “While death is less common if treatment is initiated early, survivors can still suffer from permanent kidney and liver damage.”

Prevention is essential for this zoonotic disease. Dogs of any size or breed can contract lepto and become severely ill themselves and potentially transmit it to their human companions.

How the Bacteria Spread

Worldwide, leptospirosis is on the rise in humans who work or play around water or who work with domestic animals, including livestock, and wildlife. Animals can become carriers, and humans who may be exposed to their urine should take precautions.

Until recently, dogs most at risk for becoming infected were intact male dogs used for hunting. Today, the disease is increasingly diagnosed in small-breed dogs in urban settings. Factors that may contribute to this increase in disease include exposure to rats that carry the bacteria, low rates of vaccination, and dense populations of dogs.

The bacteria that cause leptospirosis thrive in water: puddles or other standing water, outdoor water bowls, yards with heavy sprinkler use, and municipalities subject to flooding are all potential sources of transmission.

“We definitely see it more after a rainfall, but it’s being reported in little white dogs in suburban backyards more commonly and in more urban areas,” says emergency and critical care specialist Tony Johnson, DVM, who consults for Veterinary Information Network.

Large populations of urban wildlife are also factors in the spread of the disease. Dogs usually become infected with leptospirosis through direct contact with the urine of infected animals, including raccoons, rats, mice, deer, opossums, and squirrels. It’s also possible for dogs to become infected with the bacteria by swimming in or drinking contaminated water.

Dogs who have contact with contaminated soil also run the risk of the disease. That’s why even the local dog park, particularly in summer months, when the bacteria are known to thrive, can be dangerous areas to frequent. It’s equally inadvisable to let a dog sniff or drink out of sidewalk puddles or from pet water bowls outside shops.

Fencing helps to keep out wildlife that may carry the disease. It’s also important to ensure that mice and rats do not infest the property.

Clients should regularly clear underbrush and vegetation, especially along the perimeter of their property, and secure garbage bins so they can’t be raided by wildlife or roaming dogs, Dr. Bragdon says. Wearing gloves while performing these tasks can help to protect them.

Signs of Leptospirosis

Alert clients to seek veterinary help immediately if their dog shows signs of leptospirosis: vomiting, diarrhea, depression, lack of appetite, lethargy, muscle pain, increased thirst and urination, fever, and jaundice, characterized by yellowing of the lining of the mouth and whites of the eyes. Bleeding from the mouth, blood in stools, and difficulty breathing are also acute signs.

“Whenever we see a patient come in with concurrent elevations of liver enzymes and kidney values, lepto is definitely something that should be on the list of things to consider,” Dr. Johnson says.

Dogs usually exhibit signs between four and 12 days after infection. The disease tends to target younger dogs.

“It responds pretty well to simple antibiotics, amoxicillin and doxycycline,” Johnson says. “There’s an acute stage and a chronic carrier stage, and both of them have to be treated, but most patients typically do well.”

Recovery time varies. After recovery, bacteria may remain in the system, meaning that the dog is still a carrier, passing the bacteria on in urine.

“One of the main reasons we try to increase awareness is because it is transmittable to people,” Johnson says. “I’ve actually worked with somebody who had permanent liver damage from contracting lepto in a veterinary hospital, so it’s no joke.”

Leptospirosis is preventable with vaccination. Clients with small dogs may be wary of this non-core vaccine because they’ve heard it can cause reactions, but the latest vaccines are made in a way that reduces unwanted cellular debris and protein content, which are factors in vaccine reactions.

Lyme Disease

Tick populations have expanded throughout the country, and Lyme disease has become a national health hazard. It takes only one infected tick to attach to a pet or person to cause a major medical issue.

The disease can now be a year-round threat to humans and domestic animals in rural and urban areas, from private yards and dog parks to wooded areas. New suburban housing developments are increasingly infested because they encroach on fields and wooded areas that previously belonged exclusively to wildlife.

The disease attacks and inflames joints, so lameness is a common sign. A high fever is another red flag, along with lethargy, marked by a lack of typical enthusiasm and responses.

Lyme disease is transmitted by Ixodes scapularis, commonly known as deer ticks or blacklegged ticks. They can transfer infected bacteria after being attached to a pet for 24 to 48 hours. Clients should check dogs for ticks after walks or hikes in areas where ticks lie in wait.

Preventive Measures

Know the ticks in your area. And remember that summer vacation season is coming up. Clients and their dogs may be traveling to areas where blacklegged and Western blacklegged ticks are found. It’s a good idea to send out a travel alert with tips on tick prevention, including monthly tick control with chewables/pills or topical medications, as well as locales where they are likely to be found.

The Centers for Disease Control website recommends checking dogs for ticks daily after they have been outdoors. Advise clients to run their fingers through the dog’s fur with gentle pressure to seek out any small bumps, especially in the following areas on the body:

  • In and around the ears
  • Around the eyelids
  • Under the collar
  • Under the front legs
  • Between the back legs
  • Between the toes
  • Around the tail

To make the tick exam a Fear Free and enjoyable experience, they can offer their dog a small, readily consumed treat or piece of the dog’s regular food.

This article was reviewed/edited by board-certified veterinary behaviorist Dr. Kenneth Martin and/or veterinary technician specialist in behavior Debbie Martin, LVT.

Sandy Robins is an award-winning pet lifestyle journalist and author of For the Love of Cats, Fabulous Felines: Health and Beauty Secrets for the Pampered Cat, The Original Cat Bible, and Making the Most of All Nine Lives: The Extraordinary Life of Buffy The Cat.