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Capillaria Infection in Cats: A Vet’s 2025 Guide to Bladder & Lung Worms 🐾🩺

  • 188 days ago
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Capillaria Infection in Cats: A Vet’s 2025 Guide to Bladder & Lung Worms 🐾🩺

Capillaria Infection in Cats: A Vet’s 2025 Guide to Bladder & Lung Worms 🐾🩺

By Dr Duncan Houston, BVSc

🔍 What Are Capillaria Worms?

Capillaria are slender parasitic nematodes that can infect cats—commonly in the urinary bladder (Capillaria plica/feliscati) and, less often, in lungs or nasal passages (Capillaria aerophila) :contentReference[oaicite:3]{index=3}.

🐾 Where They Live & Who They Affect

  • Bladder worms (C. plica/feliscati) attach to bladder or ureter walls :contentReference[oaicite:4]{index=4}.
  • Lung worms (C. aerophila) inhabit airways, rare in cats but more common in foxes/dogs :contentReference[oaicite:5]{index=5}.
  • All ages can be infected, but bladder cases often seen in cats >8 months old :contentReference[oaicite:6]{index=6}.

⚠️ Symptoms to Watch For

Urinary Signs (Bladder Worms)

  • Frequent urination or straining to urinate
  • Blood in urine, painful urination
  • Accidents outside litter box :contentReference[oaicite:7]{index=7}
  • Possible urinary obstruction in heavy infections :contentReference[oaicite:8]{index=8}

Respiratory Signs (Lung Worms)

  • Coughing, sneezing, wheezing, difficulty breathing :contentReference[oaicite:9]{index=9}
  • Poor appetite, lethargy, fever :contentReference[oaicite:10]{index=10}

Other Variants

  • Capillaria boehmi (nasal worm): sneezing, nasal discharge :contentReference[oaicite:11]{index=11}
  • Gastrointestinal forms (e.g., C. putorii): vomiting or diarrhea—rare :contentReference[oaicite:12]{index=12}

🔬 How Cats Get Infected

All species share a similar lifecycle:

  1. Eggs from urine or feces embryonate in environment.
  2. Earthworms eat eggs—larvae develop inside.
  3. Cat ingests earthworm, transport host, or contaminated material :contentReference[oaicite:13]{index=13}.
  4. Larvae migrate → bladder (urinary species) or lungs (respiratory) and mature.

🩺 Diagnosis

  • Urinalysis: bladder worms are diagnosed by detecting characteristic eggs in urine sediment :contentReference[oaicite:14]{index=14}.
  • Fecal exam or airway lavage: respiratory species diagnosed via feces or nasal/tracheal samples :contentReference[oaicite:15]{index=15}.
  • Repeat testing may be needed—eggs often shed intermittently :contentReference[oaicite:16]{index=16}.
  • Imaging: used if complications like bladder thickening or lung inflammation are suspected.
  • Bloodwork: help evaluate overall health and support diagnostics.

💊 Treatment Options

  • Fenbendazole: off-label, commonly prescribed; effective for most Capillaria worms :contentReference[oaicite:17]{index=17}.
  • Ivermectin or levamisole: alternatives when appropriate :contentReference[oaicite:18]{index=18}.
  • Anti-inflammatories: prednisolone for symptomatic bladder inflammation :contentReference[oaicite:19]{index=19}.
  • Supportive care: fluids, pain relief, rest if respiratory distress or obstruction occurs.
  • Monitor: follow-up urine/fecal testing ensures complete clearance.

📅 Prognosis & Follow-Up

  • Generally good: most cats recover fully after deworming :contentReference[oaicite:20]{index=20}.
  • Severe bladder infections: may cause temporary urinary obstruction or cystitis :contentReference[oaicite:21]{index=21}.
  • Respiratory cases: usually mild; heavy infections may lead to bronchitis or pneumonia :contentReference[oaicite:22]{index=22}.
  • Retesting: recommended a few weeks post-treatment to confirm eradication.

🛡️ Prevention Tips

  • Keep cats indoors to reduce exposure to earthworms or rodents :contentReference[oaicite:23]{index=23}.
  • Avoid feeding raw prey or allowing outdoor hunting.
  • Maintain clean litter boxes and environments.
  • Regular deworming helps prevent uptake of parasites :contentReference[oaicite:24]{index=24}.
  • Yearly wellness exams include urine/fecal screening—early detection is key.

🐾 Tips for Cat Parents

  • Record changes in urination frequency, behavior or respiratory symptoms.
  • Ensure full medication course; never skip doses.
  • Follow your vet’s instructions on follow-up testing.
  • Provide supportive care—ease stress and comfort your cat during recovery.
  • Stay in touch via Ask A Vet for advice between visits; use calming Woopf & Purrz products.

📝 Consolidated Summary

Aspect Bladder Worms Lung/Nasal Worms
Species C. plica / C. feliscati C. aerophila / C. boehmi
Main Site Bladder, ureter Airways, lungs, nasal passages
Symptoms Straining, hematuria, accidents Coughing, wheezing, sneezing
Diagnosis Urine eggs Feces or airway sample eggs
Treatment Fenbendazole, ivermectin Fenbendazole, levamisole
Outlook Good with treatment Generally mild & treatable
Prevention Indoor life, deworming Same + minimize hunting

🐾 Help your cat stay worm‑free with expert advice from Ask A Vet—download the app for peace of mind. Ease recovery with soothing products from Woopf and Purrz.

📢 Always follow your veterinarian’s diagnosis and treatment plan.

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