Weil's Disease in Dogs

Stock Xchng; Esther Seijmonsbergen

Leptospirosis, also commonly known as Weil's Disease and Fort Bragg Fever, is an infectious disease that affects dogs, cats, humans, rodents, pigs and other animals. It damages the liver and kidneys of its victims. Some strains of the disease are increasing in the frequency.

These particular strains are being seen more often by veterinarians, while those most commonly vaccinated against seem to be decreasing.


Leptospires are bacteria that infect dogs. Some cause renal disease in dogs, while others, depending upon their type, cause liver disease. The dog gets the bacteria from coming in contact with urine or other bodily fluids of an infected animal or by coming in contact with contaminated water, food or bedding. Infections are more common in summer and fall because freezing temperatures generally destroy the bacteria.


Symptoms of leptospirosis in dogs can vary. For most pet guardians, the first noticeable symptoms are anorexia (the dog refusing to eat), vomiting, lethargy, depression, muscle pain, diarrhoea and bloody urine. Puppies and large outdoors dogs are most commonly made ill by the bacteria. In certain cases, leptospirosis can cause an infection that leads to death quickly. High fevers, shivering, painful muscles, vomiting, dehydration and shock are often seen in these instances. In less severe cases, symptoms may include cough, tonsillitis, conjunctivitis and rhinitis. Chronic renal failure and jaundice from liver damage may also occur.


Leptospirosis can be transmitted from your dog to you, meaning it is a Zoonotic disease. If your dog has leptospirosis, you should wear protective gloves when treating and caring for your pet. Your house should also be disinfected following the diagnosis. The transmission to humans usually occurs when the bacteria is inhaled, ingested or comes in contact with the skin.


Diagnosis is made through blood tests. If the dog is severely ill, dehydration and shock will be treated first. This stabilising of the pet may also include a plasma or blood transfusion. Antibiotics, generally penicillin followed by tetracycline, are prescribed to rid the bacteria from the dog's body. Oftentimes, pets must have intravenous fluids throughout their recovery. Prognosis for a pet diagnosed with leptospirosis is generally guarded.


Routine annual vaccinations protect dogs from the most common strains of Leptospirosis. However, vaccines do not protect against all strains. Keep your dog away from potentially contaminated water sources, wildlife reservoirs or domestic animals that may be infected. Mating and fighting are also common ways in which dogs contract the disease. Spaying/neutering your pet ends most of these activities and gives your dog an even better chance of avoiding leptospirosis infection.