And, if your cat is contending with kidney ailments, likes to test their hunting skills outdoors or shares a home with a dog who hikes in the woods, they, too, may be at risk for leptospirosis.
Dogs and cats can become infected in many ways, including:
• Drinking or swimming in these contaminated lakes, rivers or puddles.
• Licking their muddy paws after walking in soil contaminated with this bacteria.
• Coming into contact with urine from contaminated wildlife, such as rats, raccoons, possum, deer and skunks.
In cats and dogs, this spiral-shaped leptospira bacteria can burrow into the skin and spread through the blood and damage the kidneys, liver, blood vessels and lungs. Young pets and those with weaker immune systems are especially vulnerable. In addition, the disease can be transmitted to people — particularly children — from exposure to infected urine from dogs, cats and wildlife.
“The leptospira bacteria can survive in water and wet soil for weeks to months, particularly stagnant water,” adds Meredith Miller, DVM, ACVIM, who is board-certified in internal medicine and a lecturer of small animal medicine at Cornell University College of Veterinary Medicine in Ithaca, N.Y.
Risks and Incidences in Dogs
While mammals worldwide are at risk for becoming infected with the leptospira bacteria, the disease is more common in dogs, cattle, swine and horses than cats. Leptospirosis cases have increased slightly in humans since the 1980s, but only minor fluctuations have occurred in the number of canine cases.
What has shifted in the past decade, however, is the type of dog at the greatest risk.
“We used to consider high-risk dogs to be male, large breed and outdoor or working dogs in rural environments,” she notes. “We now are seeing smaller breed dogs in urban or suburban environments being diagnosed with leptospirosis, likely due to contact with rodents or rodent urine. Unfortunately, dogs could be exposed to leptospirosis in your own backyard.”
At Cornell, Dr. Miller said she has treated only one dog for leptospirosis — a small dog from a suburban area.
“The dog presented for acute renal failure and fortunately, responded well to antibiotics and aggressive supportive care,” adds Dr. Miller.
And if you have a multi-species household, what’s the risk of your dog passing on this bacterial disease to your cat?
Curiously, cats rarely develop leptospirosis for reasons still unknown to veterinarians and medical researchers. Dr. Miller points out that cats have been shown to develop antibodies in their blood against the bacterial infection.
“Although cats rarely show clinical disease, a recent study demonstrated that a higher percentage of cats with kidney disease were positive for leptospira bacteria compared to healthy cats,” Dr. Miller says. “The study suggests that leptospirosis should be considered as a potential under-diagnosed cause of kidney disease in cats.”
She urges people to supervise their cat’s outdoor access, and practice good hygiene when cleaning the litter box or cat urine off flooring in their homes. She advises people to wear rubber gloves to avoid contact with urine and to thoroughly wash their hands after scooping the litter box to reduce the risk of contracting leptosporisis.
Look Out for These Signs
Leptospirosis takes time — up to seven to 10 days after being exposed through infected urine — to show signs in an infected dog. And some dogs and cats may not show signs, making this a disease tricky to diagnose.
Take your pet to your veterinarian for a complete examination if your pet comes into contact with mice or rats and displays any of these symptoms:
• Moving stiffly or showing pain when walking
• Coughing or wheezing
• Discharge from the nose or eyes
• Reduced appetite and water intake
A veterinarian will likely perform blood and urine tests to rule out other conditions with similar symptoms. The veterinarian will also most likely inquire about the pet’s habits. Does he go outdoors unsupervised? Does he like to hunt and kill mice or rats? Be sure to relay such information to help the veterinarian in pinpointing the disease and providing treatment quicker.
“The diagnosis can be tricky as false negatives can occur in the acute or early course of the disease,” says Dr. Miller.
Effective Treatment: Antibiotics
While the primary treatment for leptospirosis in cats and dogs is antibiotics, some dogs may also need intravenous fluids and medications to combat possible nausea, to increase their appetites, to correct electrolyte imbalances and rehydrate them. The quicker the pet receives antibiotics and other necessary treatments, the faster his chance for recovery and the less likely any organs will suffer damage from the bacteria.
“Fortunately, leptospirosis has not become resistant to the antibiotics we commonly use to treat it,” Dr. Miller says.
Prevention Is Key
You can’t keep cats and dogs in protective bubbles. They need and deserve to live in environments that provide them with mental and physical enrichment. One effective option to reduce a pet’s risk is the leptospirosis vaccine that must be given each year to maintain its effectiveness. However, the vaccine does not provide 100% protection. The reason is that there are many types of leptospires, and the current vaccine does not deliver immunity against all these types.
“The vaccine is a bacterin, meaning it is made from killed leptospira bacteria,” explains Dr. Miller. “The vaccine protection lasts for one year, so annual boosters are necessary to continue to prevent disease. This is not a ‘core’ or mandatory vaccine, but one recommended for dogs and cats considered at risk for leptospirosis.”
In addition to the vaccine, take these steps to reduce your dog’s risk for contracting the leptospira bacteria:
• Note any subtle changes in the pet’s behavior and book wellness exams with his veterinarian at least once a year, ideally, twice a year.
• Do not allow your dog or cat to drink from puddles, lakes or other water sources that may be contaminated. In a multi-pet household, a dog returning from a hike can have the bacteria on his paws and pass it on to other household pets. Get in the habit of cleaning his paws with a damp washcloth.
• Work with a pet-friendly pest control company to reduce the chance of mice, rats or other rodents on your property. Your dog may develop this disease if he comes into contact with an infected rodent.
• When cleaning up any urinary accidents from your dog, wear rubber gloves, and wash your hands afterwards in warm, soapy water
• Clean and dry food and water bowls daily.
• Avoid picking up or handling stray cats you encounter outdoors.
Leptospirosis in People
Cases of leptospirosis have increased worldwide since the 1980s in people and animals, with outbreaks generally occurring in periods of wet as well as hot, humid weather, according to the U.S. Centers for Disease Control. The most common season is in the fall, and cases are more often seen in the Pacific Northwest, Texas, the Midwest and Northeast.
People who work outside or with animals, such as farmers, sewer workers, slaughterhouse workers and veterinarians, are more at risk for this disease.
In people, this bacterial disease can occur through contact with urine from infected animals or contact with contaminated water, soil or food. While some infected people may show no symptoms, leptospirosis can cause:
• Elevated fever
• Chills and muscle aches
• Abdominal pain and diarrhea
In extreme cases, a person may suffer meningitis or kidney or liver failure if the disease is untreated. Antibiotics, such as penicillin or doxycycline, are used to treat this infection.
By Sarah Zumhofe