Fact sheet about Leptospirosis in dogs and people

This fact sheet is for people whose dogs have been diagnosed with or might have leptospirosis. The bacteria that cause Leptospirosis have been found in cattle, pigs, horses, dogs, rodents, and wild animals. Leptospirosis is an important disease passed from animals to people. Outbreaks of disease in humans are usually caused by exposure to water contaminated with the urine of infected animals. This disease can be transmitted from dogs to people, but it is rare that this happens. If you know the facts, you can help prevent people or other dogs from getting this disease.

What is leptospirosis?

Leptospirosis is a disease caused by bacteria (germs) that can be found in all mammals. The bacteria are spread through the urine of infected animals or people, and can live in polluted water. Some people may get leptospirosis from touching or swallowing water that has these bacteria. People can also get this disease through direct or indirect contact with the infected urine of people or dogs. The bacteria can get into a person’s body through eating or drinking food or water with these bacteria, through a cut in the skin, or through mucous membranes (eyes, nose, mouth, or anus).

Who is at risk of getting leptospirosis?

People at higher risk of getting leptospirosis include veterinarians, sewer workers, and farmers. Livestock infected with leptospirosis can be a risk to people exposed to livestock. Dogs are known to get leptospirosis, and they can also pass the infection on to people. People with dogs that have or might have leptospirosis should protect themselves.

What are the signs of leptospirosis in dogs?

The signs of leptospirosis in dogs vary. Your dog may not have any symptoms, or it may get severe, life-threatening infections of the liver and kidneys. Some dogs can continue to have the bacteria in their urine for a year. Most dogs will stop shedding the bacteria in their urine 24 hours after having antibiotic treatment.

What if I think my dog has leptospirosis?

Call your veterinarian right away. Your veterinarian can do tests to see if your dog has this disease.  Leptospirosis can be treated with antibiotics and other medicines.

How did my dog get leptospirosis?

Your dog probably got the infection indirectly from wildlife. Wild animals like rats or raccoons have the bacteria in their urine, and the bacteria get in puddles, ponds, or other water. Your pet may have come into contact with it by drinking contaminated water (water with the bacteria), swimming in it, or walking through it. Dogs may also pass this disease to each other.

It is not likely that you will get leptospirosis from your dog. However, human cases of leptospirosis from dogs can happen, and they can be serious. Since untested dogs can have the leptospirosis bacteria in their urine for months, the risk of passing the disease to you (transmission) may exist for several months. It is important for you to protect yourself, your family, and your friends.

Can other pets get leptospirosis?

Yes.  Other mammals are also at risk of getting leptospirosis. Once an animal has had leptospirosis, it can get it again.

What about leptospirosis in people?

The time between exposure to the bacteria and development of disease is usually 1 to 2 weeks. It can be as short as 2 days or as long as 4 weeks. Signs of leptospirosis in people vary, although it usually comes on quickly, and most people feel like they have the flu with an upset stomach.

The disease can stay mild, or it can get much worse. It can give you serious, life-threatening infections of the kidneys, liver and brain. Most people are sick from 1 to 3 weeks. People may pass the bacteria in their urine for about 1 month, although some people may pass it for as long as 5 months. People can also get leptospirosis from other infected people, but this is rare. Leptospirosis can be treated with antibiotics and other medicine. If you think that you might have this disease, call your doctor right away.

How can I protect myself and other people when my dog has leptospirosis?

Because leptospirosis bacteria are passed in urine, splashing of urine plays an important role in spreading this disease. Here is what you can do:

  • DO NOT let your dog urinate in or near ponds, pools, or puddles.
  • Keep your dog away from vegetable gardens.
  • Keep your dog away from playgrounds, sandboxes, wading pools and other places where kids may play.
  • ALWAYS wash your hands after touching your dog or anything that might have your dog’s urine on it.
  • If you are cleaning where there is dog urine, use an anti-bacterial cleaning solution or a solution of 1 part bleach in 10 parts water.
  • Make sure that your dog takes ALL of its medicine.

How can I prevent leptospirosis in my dog?

  • Keep rodents (rats, mice, or other animal pests) under control. Rodents are known to carry the bacteria.
  • Keep your dog away from ponds, puddles, or other standing water.
  • Keep your garbage covered, and don’t feed your pets outside. This will help keep wild animals away from your house and pets.

Is there a vaccine for dogs?

There is a vaccine, and you should make sure that your dog is vaccinated against leptospirosis. However, because there are many strains (types) of the bacteria the vaccine may not give 100% protection, and protection may last for less than one year. If your dog gets leptospirosis, it can still get sick again with a different strain of leptospirosis. Dogs with free access to ponds and other bodies of water in areas where the bacteria is present may need to be vaccinated more often.

Where can I get more information?

  • Your veterinarian
  • Your doctor, nurse or health center
  • The Massachusetts Department of Public Health, Division of Epidemiology and Immunization at (617) 983-6800 or on the MDPH website at http://www.mass.gov/dph
  • The Massachusetts Department of Agricultural Resources, Bureau of Animal Health at (617) 626-1795

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