Leptospirosis in Dogs

Written and verified by the lawyer Francisco María García

Last update: 21 December, 2022

Leptospirosis in dogs, also known as canine typhus, is a contagious disease that causes severe disorders in the body. It is considered to be a public health issue because it poses a high risk of infection among different species and it has a high fatality rate.

Currently, leptospirosis in dogs is partially controlled in Europe and America. These continents have reduced the diagnoses with pet vaccination campaigns and free treatment for infected people.

What is leptospirosis in dogs?

Leptospirosis in dogs is a bacterial, infectious, and severe disease. Public Health considers this disease to be the largest zoonosis worldwide because it affects reptiles, birds, amphibians, mammals, and even humans.

This disease is caused by several serotypes of a bacteria that belongs to the Leptospiraceae family, of the Spirochaetales order. Those that affect dogs the most are known as Leptospira Canicola and Leptospira Icterohaemorrhagiae.

Origin of the disease

A pathogen enters the body through mucous membranes or skin injuries, then moves throughout several parts of the body until it settles down in the kidney and liver tissues. Afterwards, the dog eliminates the disease through its infected urine, which makes it capable of infecting anyone who comes into contact with it.

The serotypes of this bacterial family have spread all around the world, affecting animals of all species. They cause different clinical syndromes such as Weil’s disease, 7-day fever, harvest fever, Fort Bragg fever, field fever, and rat catcher’s yellow. Leptospirosis is the generic name for all of these disorders and their clinical manifestations.

How do dogs catch leptospirosis?

As mentioned earlier, Leptospira spreads in the affected animal’s kidney and is then eliminated in the dog’s urine. Therefore, having direct contact with the infected urine or with contaminated water and floor particles is the main cause of contamination.

Rats are the main transmitting hosts. They can spread these bacteria into the environment without having any symptoms. So, most cases of leptospirosis in dogs and humans are due to having contact with infected rat urine.

What are the main symptoms of leptospirosis in dogs?

The incubation period of leptospirosis in dogs and humans is usually between one to three weeks. There are two main symptomatic stages in diagnosed cases of leptospirosis in dogs.

1st stage: Generic symptoms

At the beginning, leptospirosis in dogs starts appearing through generic symptoms that can resemble a cold. Thus, the dog experiences headaches, loss of appetite, fever, vomiting and/or nausea, muscle aches, and fatigue.

2nd stage: Specific symptoms according to the Leptospira serotype

At this stage, the most severe symptoms affect the animal, according to the Leptospira serotype. After the first symptoms, the dog usually starts showing more severe signs in his health such as the following:

• Eye irritation
• Canker sores and nasal mucous
• Stiffness in the neck
• Intestinal and/or pulmonary hemorrhages
• Bloody diarrhea
• Arrhythmia or heart failure
• Kidney failure
• Difficulty breathing

Progress of the disease

As the disease advances, the dog can develop severe secondary illnesses such as meningitis or jaundice. The latter usually gives a yellowish coloring to the eyes and skin.

It is important to go to the veterinarian immediately if you pet shows any changes in his normal behavior. Therefore, you can get an early diagnosis that gives a clear picture of the disease and increases the treatment options without any health complications.

How to prevent leptospirosis in dogs

Prevention is of utmost importance when it comes to containing leptospirosis in dogs and most of the zoonosis. For that reason, vaccination is crucial to keep your pet healthy and protect the well-being of everyone around him.

What is the treatment for leptospirosis in dogs?

The main treatment for leptospirosis in dogs consists of antibiotics that fight the bacterial infection, such as penicillin or streptomycin. However, in severe cases, greater measures are necessary to heal and/or stop liver and kidney damage as well as opting for a low-protein diet.

So, it’s worth remembering that the veterinarian is the only professional that should prescribe a specific and proper treatment for each animal.