Leptospirosis is a zoonotic infectious disease caused by leptospira bacteria which affect domestic pets and wild animals including rats, raccoons, opossums, deer, skunks, cattle, pigs and foxes. Wild animals often function as asymptomatic reservoir hosts for leptospirosis, and as dogs and people gain greater exposure to wildlife, their risk of getting leptospirosis increases. The disease is somewhat rare in cats, but felines do produce antibodies against leptospirosis serovars (bacteria).
Leptospirosis is most often present in warm, humid regions, especially in marshy areas with bodies of standing water (lakes, pools, puddles or ponds) and where there are large populations of roaming wildlife. Dogs can become infected when swimming in, playing in or drinking contaminated water, and typically through contact with the urine of an infected animal – which can remain contagious in soil for up to 6 months. Direct spread of infection is enhanced by crowding of animals in situations such as kennels. Leptospirosis infections are more common in the summer and early fall and after periods of flooding, with a high incidence reported in dogs playing in and around lakes.
Not all dogs exposed to the bacteria will develop symptoms. Dogs affected by leptospirosis will typically display signs between 4-12 days after exposure, though some of the milder symptoms may pass. Recovered dogs intermittently excrete leptospires in their urine for months after initial infection. A lingering infection can cause serious damage to the animal’s liver and kidney function, however. And, in a small number of severe cases, leptospirosis can be fatal. The hallmark of leptospirosis in dogs is kidney dysfunction, and sometimes, depending upon the serovar, liver dysfunction.
What are the Symptoms of Leptospirosis in Dogs?
- Fever and reluctance to move
- Muscle stiffness and pain
- Vomiting and diarrhea
- Loss of appetite
- Jaundice (yellowing skin)
- Blood in urine, vomit, saliva or poop
- Increased thirst and urination
- Weakness and trembling
- Eye inflammation
- Difficulty in breathing, runny nose, coughing and nose bleed
If your dog displays any of the above symptoms and has recently been in contact with potentially contaminated water, you should consult with your vet as soon as possible. He or she will request a full medical history and perform diagnostic tests including blood work and a urinalysis to confirm the diagnosis.
Dogs that become seriously ill with leptospirosis should be hospitalized for fluid therapy to help with hydration. Your vet will prescribe broad spectrum antibiotics for a period of at least 4 weeks and provide supportive care to treat any other symptoms present (such as vomiting and fever) with the appropriate medications.
Leptospirosis is a zoonotic disease which means it can be transferred to humans and other animals through contact with infected bodily fluids (not including saliva). Keep pets in a cage during recovery, isolated from children and away from any other household pets until the prescribed antibiotic therapy is completed. Always use protective gloves while handling an infected pet and be sure to use disinfectant (iodophore disinfectants such as Betadine are best) when cleaning up any and all places that come into contact with their bodily fluids.
Bear in mind that pets recovering from leptospirosis can shed the infection for several weeks after treatment. There are 100-200 cases of leptospirosis in humans each year, who exhibit flu-like symptoms when infected. Consult your family physician for additional guidance if your pet has suffered with lepto in the last 12 months.
The Leptospirosis Vaccine
The leptospirosis vaccine is recommended for pets whose lifestyle (hunting or working dogs) or geographic location put them at a higher risk of infection.
There is some discussion in the veterinary community regarding the efficacy of the leptospirosis vaccine and potential adverse reactions. The efficacy of the vaccine is dependent upon the serovars it is active against. There are now vaccines against four serovars of leptospires in dogs, whereas until recently they were effective against only two serovars. Leptospirosis vaccines used to be chemically inactivated whole cultures, which made them relatively allergenic in comparison with the tissue culture of viral vaccines. Better filtration mechanisms have made this vaccine safer and less allergenic than before. Understanding the benefits and possible risks of any medication is part of being a pet parent, and it is important to acknowledge that no vaccine provides 100% protection against infection. Book a consultation with your veterinarian to determine your pet’s risk of exposure to leptospirosis so you can make an informed decision about your pet’s vaccination needs.
Aside from medication, limiting your dog’s access to stagnant water and wildlife (especially raccoons and rodents) is the best means of protection against a possible lepto infection.