Leptospirosis and Rat Season 2026: Why This Autumn Is the Right Time to Talk to Your Vet

What Leptospirosis Is

Leptospirosis is a bacterial infection spread through rat urine. Infected rodents contaminate soil, puddles, and stagnant water — dogs pick it up simply by splashing through a puddle or sniffing wet ground after a rat has passed.

• Once inside the body, the bacteria attack the kidneys and liver
• The original Sydney outbreak had an 88% case fatality rate — the majority of affected dogs did not survive even with intensive care
• It is also zoonotic — it can pass from dogs to humans

This Is a Surry Hills Story

Leptospirosis had not been reported in Sydney since 1976. When it re-emerged in 2017, the epicentre was right here. University of Sydney research identified a primary cluster within a 1.1km radius of Surry Hills and Darlinghurst, expanding to cover Chippendale, Eveleigh, and Redfern.

The parks named in the research as most frequented by seropositive dogs were Ward Park, Prince Alfred Park, Redfern Park, and Moore Park — the same parks local dogs visit every day.

Vets on Crown contributed cases to the original University of Sydney research. This is a disease our team has seen first-hand.

Why Autumn 2026 Is Higher Risk

• Rodents move indoors as temperatures drop — into the terrace houses, laneways, and restaurant back-of-house areas along Crown Street, Bourke Street, and Cleveland Street
• Autumn rainfall washes contaminated rodent urine into gutters, puddles, and park soil
• The March 2026 APVMA rat bait restrictions mean stronger products are off supermarket shelves — some residents may be less effective at managing rodent populations this winter, putting more contaminated rodents in the environment
• After any rain in Surry Hills, Redfern, or Darlinghurst, almost every gutter, laneway, and park corner becomes a potential exposure point

Is your pet showing signs of Leptospirosis or concerned about your pet's recent interactions this autumn season? Vets on Crown on Surry Hills offers Vaccinations that could save their lives. We also offer Consultations for your peace of mind.