Leptospirosis in Dogs: What North Rocks Pet Owners Need to Know

At North Rocks Veterinary Hospital, we are committed to protecting pets across North Rocks, Baulkham Hills, Oatlands, Dundas, Carlingford, West Pennant Hills, Parramatta, and surrounding areas. One disease that has re-emerged in Greater Sydney in recent years; and is now an important part of preventive care discussions. Is Leptospirosis.

Here’s what local dog owners need to know.

What Is Leptospirosis?

Leptospirosis is a serious bacterial infection caused by Leptospira species. It affects many mammals, including dogs and humans, and is considered zoonotic (meaning it can spread from animals to people).

The bacteria are typically spread through:

• Contact with rodent urine
• Contaminated soil or mud
• Stagnant or slow moving water
• Flood affected environments

Dogs can become infected when the bacteria enter through the mouth, nose, eyes, or small cuts in the skin.

With bushland reserves, creeks, urban wildlife, and increasing rodent populations throughout parts of Sydney’s North West, environmental exposure risk has increased compared to previous decades.

Why Is This Relevant to North Rocks & Greater Sydney?

For many years, Leptospirosis was considered uncommon in Sydney dogs. However, since 2017, confirmed canine cases have re-emerged in Greater Sydney and surrounding coastal regions.

Clinical case investigations and research, including work led by Christine Griebsch at the University of Sydney have documented:

• Dozens of confirmed canine cases across NSW since 2017
• Clusters within metropolitan Sydney
• A significant case fatality rate in severely affected dogs

This re-emergence has changed how veterinarians across Sydney approach prevention.

Symptoms of Leptospirosis in Dogs

Leptospirosis can range from mild to life threatening. Early signs are often vague, which can delay diagnosis.

Common symptoms include:

• Fever
• Lethargy
• Vomiting or diarrhoea
• Loss of appetite
• Increased thirst or urination changes
• Jaundice (yellow gums or eyes)
• Abdominal pain

Severe cases may progress to:

• Acute kidney failure
• Liver failure
• Bleeding disorders
• Multi organ dysfunction

Prompt veterinary care is critical. Early intervention significantly improves survival rates.

How Is It Treated?

Treatment typically involves:

• Hospitalisation
• Intravenous fluids
• Antibiotics (such as doxycycline or penicillin derivatives)
• Monitoring of kidney and liver function
• Supportive care for complications

Even with intensive treatment, Leptospirosis can be fatal in severe cases, which is why prevention is so important.

Lepto 2 Vaccine

One commonly used Leptospirosis vaccine in Australia is Lepto 2, Leptospirosis is now considered a core vaccine.

Vaccination Protocol

• Initial course: Two injections given 3-6 weeks apart
• Protection develops approximately 3 weeks after the second dose
• Annual boosters are required to maintain immunity

Because newer NSW data shows increasing involvement of serogroup Australis, vaccine selection and recommendations should always be discussed with your veterinarian to ensure appropriate coverage based on current local risk.

Is My Dog at Risk in North Rocks?

Risk factors include:

• Access to parks, bushland, or waterways
• Hunting or exposure to rodents
• Drinking from puddles or creeks
• Living in areas with increased rodent activity
• Flood prone environments

Even suburban dogs with backyard access can be exposed.

Given the documented Sydney cases since 2017, leptospirosis vaccination is now considered an important preventive discussion for dogs in our region. The most recent case in Manly Mosman 2026.

Prevention Beyond Vaccination

In addition to vaccination:

• Avoid allowing dogs to drink from stagnant water
• Reduce rodent attractants around your home
• Secure bins and pet food
• Seek veterinary care promptly if your dog becomes unwell

Our Commitment to Preventive Care

At North Rocks Veterinary Hospital, our approach is guided by current research, evolving NSW case data, and our commitment to proactive protection.

If you would like to discuss whether Leptospirosis vaccination is appropriate for your dog, our team is happy to help you make an informed decision based on lifestyle, location, and the latest local evidence.