Protecting Your Pet from Heartworm and Leptospirosis
Southern California’s sunshine comes with more than just great weather—it also brings year-round exposure to two sneaky but preventable diseases: heartworm and leptospirosis. Both can be life-threatening for pets, and one can even spread to people. Read on or watch the video from Dr. Moreno below for what you need to know to keep your dog or cat safe.
Heartworm: A Silent Threat
Heartworm disease is caused by parasitic worms that take up residence in a pet’s heart, lungs, and blood vessels. It spreads through mosquito bites—so even pets who stay mostly indoors are at risk.
How it happens:
When a mosquito carrying heartworm larvae bites your pet, those microscopic larvae enter the bloodstream. Over several months, they mature into long worms that damage the heart and lungs, leading to serious illness.
What to watch for:
Coughing
Fatigue or reluctance to exercise
Difficulty breathing
In severe cases, heart failure or sudden death (especially in cats)
Prevention is simple:
A monthly heartworm preventive, given year-round, is the most effective protection. Pair that with an annual heartworm test to ensure your pet stays healthy and parasite-free.
Leptospirosis: A Rising Concern
Leptospirosis (often called “lepto”) is a bacterial disease spread through the urine of infected wildlife such as rats, raccoons, and coyotes. Pets can become infected by drinking, swimming, or even walking through contaminated water or damp soil—yes, even that puddle at the dog park.
Symptoms can include:
Fever
Vomiting
Lethargy
Jaundice (yellowing of the skin or eyes)
Kidney or liver failure in severe cases
Leptospirosis is zoonotic, meaning it can spread from animals to people, making prevention even more important for families with pets.
Protection plan:
Annual lepto vaccination for dogs, especially those who spend time outdoors or live near wildlife.
Avoid standing water when possible.
Why Prevention Matters More Than Ever
Both heartworm and leptospirosis have been on the rise in Southern California in recent years. Fortunately, both are highly preventable with consistent care and early detection.
If you’re unsure whether your pet is protected, our team at Hamilton Animal Hospital can help. We’ll review their records, update their vaccines or prevention plan, and make sure you have everything you need to keep them healthy all year long.
We’re Here for Your Pet’s Health
Preventive care is one of the best gifts you can give your pet. Schedule an appointment today to make sure your dog or cat is protected against heartworm and leptospirosis. Together, we can keep those tails wagging and whiskers twitching for years to come.
