Lungworm advice for dog owners

What is Lungworm?

Lungworm has been a common problem in southern areas of England and South Wales for some time, but the number of cases diagnosed in northern England and Scotland has risen too, so people all over the UK should be aware of lungworm.

How do dogs get lungworm?

Dogs get lungworm by eating larvae found in infected snails, slugs or frogs. They can also accidentally eat infected tiny slugs if they are on a toy or their fur.

The lungworm larvae then grow inside the dog and adult lungworms move through their body to live in their heart and blood vessels. This can cause heart problems, breathing problems and pneumonia but in mild cases infection can remain unnoticed by owners. After about 28 days the worms start to produce their own larvae which can lead to serious problems. 

It can cause haemorrhages in the lungs, liver, intestine, eyes and spinal cord but also pretty much anywhere in the body. If left untreated, it can be fatal in severe cases.


Symptoms of lungworm in dogs 

Diagnosing lungworm can be difficult because symptoms vary but they can include:


  • coughing
  • breathing problems
  • reluctance to exercise
  • if a dog gets a minor injury, like a small cut, it might bleed for longer
  • abnormal blood clotting

Vets can also examine a sample of the dog’s faeces under the microscope to help diagnose lungworm, although this isn’t 100 per cent reliable as there aren’t always lungworms present in every sample.

Dogs can’t pass the disease directly from dog to dog but they will pass the larvae in their waste. This then infects more slugs and snails who are eaten by more dogs, so the disease can rapidly spread within dog communities.

Preventing lungworm in dogs 

Talk to your vet about regular lungworm treatment and prevention from lungworm, particularly if you travel with your dog around southern England or South Wales.

If you spot slugs and snails in your garden or local parks then be extra vigilant when out with your dog and always consult your vet as soon as possible if your dog becomes unwell.

Can humans get lungworm?


No, lungworm is not known to infect humans. There are, however, other types of worms - roundworms, tapeworms, hookworms and whipworms - which can be transmitted from pets to humans, so it's crucial that regular worming takes place at least four times a year. Some tapeworms can also be passed on through infected fleas, but this can be prevented with regular flea treatment. Find out more about basic healthcare in dogs.



Puppy Alfie in a garden
— Page last updated 17/01/2022