Hookworms in Cats and Dogs: A 2025 Veterinary Guide to Prevention, Treatment, and Zoonotic Risk 🐶🐱🩸

Hello, I’m Dr Duncan Houston BVSc. Hookworms are common intestinal parasites in pets, but their danger lies in how they feed—by sucking blood. In young animals, hookworms can cause fatal anemia. Some strains are now drug-resistant, and they can even infect humans. Let’s dive into this serious parasite, its life cycle, symptoms, treatment, and what you can do to protect your pets and family. 🧫🩺

🧬 What Are Hookworms?

Hookworms are parasitic worms that attach to the small intestine using sharp teeth and drink blood from the intestinal wall. They include:

• Ancylostoma caninum – most severe, in dogs
• Ancylostoma braziliense – affects dogs and cats, zoonotic
• Uncinaria stenocephala – less aggressive

They’re part of the “big four” puppy parasites: hookworms, roundworms, tapeworms, and coccidia.

🦟 Life Cycle & Transmission

• 🥚 Eggs pass in stool and hatch into larvae in soil
• 🪱 Larvae become infective (L3 stage)
• 🐾 Dogs/cats are infected by:
• 🦶 Skin penetration (feet, belly)
• 👅 Licking contaminated soil
• 🐁 Eating infected prey (rodents, insects, cockroaches)
• 🫁 Larvae may migrate to lungs, get coughed up, swallowed, and settle in the intestine
• 🥚 Female worms lay eggs in the intestine—cycle repeats

⚠️ Only worms in the intestines are vulnerable to deworming meds. Dormant (encysted) larvae can “leak” into the intestine later. 🩸

🐶 Hookworms in Puppies & Kittens

Puppies: Most infected . Pregnancy hormones trigger dormant larvae in the dam to migrate into pups. 🍼

Kittens: Usually infected by eating larvae or infected prey, not through nursing. 🐱

🩸 Symptoms

• 🤍 Pale gums
• 🥱 Weakness or collapse
• 📉 Weight loss
• 💩 Diarrhea (may or may not be present)
• 🧊 Potbelly in young pets

💡 Severe blood loss can kill a puppy if not treated quickly. Transfusions may be needed. 🩺

💊 Treatment & Dewormers

Commonly used dewormers include:

• 💊 Pyrantel pamoate (oral)
• 💊 Fenbendazole (Panacur®, oral)
• 💊 Milbemycin oxime (Interceptor®, oral)
• 💉 Moxidectin (Advantage Multi®, ProHeart®, topical/injectable)
• 💊 Mebendazole (less common)

Note: Puppies should be dewormed every 2 weeks starting at 2 weeks old until 8 weeks, then monthly. 🗓️

Severely affected puppies may also need:

• 🩸 Blood transfusions
• 🧃 Iron supplements
• 🍲 Nutritional support

🧪 Drug Resistance Alert

Some retired racing greyhounds have hookworms resistant to common treatments. These strains are spreading to other dogs. 🧬

Resistant Hookworm Signs:

• Persistent infections despite treatment
• Recurring anemia or diarrhea

Fecal Egg Count Reduction Test (FECRT) compares egg counts before and after treatment to assess resistance. 🧫

Moxidectin-based products (Advantage Multi®, ProHeart®) may still work if the dog has not previously received them. 🛡️

🧍‍♂️ Hookworms in Humans

• 🦶 Cutaneous larva migrans: itchy skin condition from larvae penetrating skin
• 🥗 Humans can also get intestinal hookworms from contaminated food
• 👣 Avoid walking barefoot in areas pets defecate

Hookworm infections in people are treatable but unpleasant. Clean up after your dog immediately and wash hands after contact. 🚿

🧼 Environmental Control

• 💩 Pick up poop immediately to break the life cycle
• 🌬️ Eggs die in dry or freezing conditions (unlike roundworms)
• 🧹 Keep yard clean and grass short
• 🛑 Avoid gardening barefoot or letting children dig in pet areas

📅 Prevention Tips

• 🐶 Start puppies on monthly dewormer at 8 weeks
• 🐱 Deworm kittens starting at 2 weeks
• 🩺 Combine heartworm prevention with intestinal dewormers
• 🧴 Use flea/tick products to prevent vector exposure

📱 Ask A Vet: Support for Hookworm Concerns

• 🧪 Interpret fecal egg counts
• 💊 Plan combo treatment for stubborn infections
• 📋 Monthly deworming schedule setup
• 👣 Environmental hygiene strategies

Visit AskAVet.com or download the app for fast answers. 📲

✅ Summary: Hookworms in Dogs & Cats

• 🩸 Hookworms feed on blood—can cause fatal anemia
• 🧬 Infections may come from nursing, soil, prey animals
• 💉 Treat with pyrantel, fenbendazole, milbemycin, or moxidectin
• 🧪 Drug-resistant strains require special testing
• 🧼 Environment must be cleaned regularly
• 🦶 Humans can be infected—wear shoes, wash hands

Hookworms are deadly to puppies, zoonotic for people, and increasingly drug-resistant—so regular prevention is vital. 🐶🐱🛡️

— Dr Duncan Houston BVSc