Lungworm

Lungworm (Angiostrongylus vasorum) is a parasite that can cause serious, sometimes fatal, disease in dogs. Awareness has increased significantly in recent years as cases have spread across the UK, and it's a condition we take seriously in this area.

How dogs become infected

  • Lungworm larvae are carried by slugs and snails.

  • Dogs become infected by eating slugs or snails directly, or accidentally — for example, small slugs or snail trails on grass, toys, water bowls left outside, or garden vegetables.

  • Puppies and young, curious dogs who scavenge or eat grass are often at higher risk, but any dog can be affected.

Signs of lungworm

Signs can vary widely and may develop gradually, which can make lungworm easy to miss initially:

  • Coughing

  • Breathing difficulties or reduced exercise tolerance

  • Lethargy or reluctance to exercise

  • Poor blood clotting — including unexplained bruising, bleeding from small wounds that won't stop, or nosebleeds

  • Weight loss

  • In severe cases, collapse or sudden death

Because lungworm can affect the lungs, heart and blood clotting system, symptoms can sometimes be mistaken for other conditions, which is why we consider it in dogs presenting with unexplained coughing, breathing changes or bleeding problems.

Diagnosis

  • Blood tests, including specific antigen tests

  • Faecal testing to look for larvae

  • Sometimes alongside chest X-rays or other investigations, depending on symptoms

Treatment

  • Lungworm is treatable with appropriate anti-parasitic medication, particularly if caught early.

  • Severe cases, especially those involving bleeding disorders or heart/lung complications, may need more intensive supportive treatment and hospitalisation.

  • Prognosis is generally good with prompt treatment, but severe or advanced cases can be life-threatening.

Prevention

  • Not all standard wormers cover lungworm — a specific licensed product, given at the correct interval, is needed for protection.

  • Year-round, consistent prevention is recommended, since exposure risk exists throughout the year, not just in warmer months.

  • Try to discourage your dog from eating grass, scavenging, or drinking from puddles and outdoor water bowls where slugs and snails may have been.

  • Regularly clean water bowls and pick up dog toys left outside overnight.

Still have questions?

If you're unsure whether your dog's current worming treatment covers lungworm, or you've noticed any of the signs above, please contact us on 01797 252321.