Lungworm in dogs is a serious and potentially fatal disease. Dogs get infected by eating slugs or snails carrying larvae of the parasite Angiostrongylus. Common symptoms include coughing, breathing problems and unexplained bruising. Young, curious dogs and puppies are most at risk.

87% of UK vets have seen cases of lungworm in dogs, with 30% reporting deaths. The numbers and spread of cases are increasing every year. Symptoms of lungworm are varied and early stages are easily-mistaken for other illnesses. The best way to protect your dog against lungworm is with regular preventive care, using a vet-prescribed wormer. Always seek prompt veterinary advice if your dog develops a new and persistent cough or unexplained bruising.

What is Lungworm in dogs?

Angiostrongylus vasorum is the most common lungworm in the UK . Adult lungworms live inside your dog’s heart and the major blood vessels going to their lungs. You won't see evidence of these worms until your dog starts to cough.

• Snails and slugs carrying Angiostrongylus larvae are found all across the UK, but more so in certain regions.

• When a dog or fox eats a snail or slug, the larvae migrate from the intestines through the liver and into the bloodstream.

• When larvae reach the heart, they mature into adults.

• Adult worms breed in the heart. Their eggs hatch into larvae which enter the airways.

• From the lungs, the larvae are coughed up, swallowed, and pass out of the body in poo.

• There the larvae can infect passing slugs and snails.

How do dogs get lungworm?

• By eating slugs or snails infected with Angiostrongylus larvae

• Eating grass with slugs on it or drinking from puddles containing lungworm larvae

• Licking slime trails: the sticky slimy substance produced by slugs

• Eating food or drinking from bowls contaminated with snail slime

• Playing with and licking toys which have been left outside overnight, exposed to slugs

What time of year has the most risk?

The risk is present all year round. However:

• Slugs hatch in February and breed August-September, then die off

• Slugs are most active in mild damp conditions

• Dogs pick up the parasite in summer and autumn, when slugs are abundant and larvae mature.

• Vets diagnose most coughing lungworm cases in winter and spring

Climate change is bringing milder, damper weather, favouring slug activity and year-round breeding.

Why does Lungworm make dogs sick?

• Migrating larvae damage the tissues and blood vessels they pass through as they make their way towards the heart. This triggers inflammation.

• Adult worms damage the heart and blood vessel walls.

• Worms in blood vessels interfere with circulation of blood to the lungs. Poor blood circulation in the lungs means less oxygen gets into the body.

• Your dog’s body fights the invading larvae and adult worms. Sometimes this immune reaction is so severe, it worsens the inflammation.

• Severe immune reactions can result in problems with blood clotting, uncontrolled bleeding and organ failure.

Are there other types of lungworm in the UK?

Other lungworms are very rare in the UK but include:

Oslerus osleri

• Lives in the windpipe (trachea) and larger airways

• Transmitted from bitches to pups in saliva during grooming

• Usually found in dogs under 2 years old

Crenosoma vulpis or Fox Lungworm

• Lives in windpipe and airways

• Infection from eating slugs or snails or a creature which has eaten these

Symptoms of Lungworm infection in dogs

Symptoms of lungworm in dogs range from mild to life-threatening. The severity and type of symptoms depends on:

• The number of worms present

• What parts of the body the larvae reach

• The intensity of your dog’s immune response.

Symptoms include:

• Coughing in about 70% of cases; lasting weeks to months

• Breathing difficulties: fast, laboured, heavy or noisy breathing in 23% of cases

• Unexplained or prolonged bleeding and unexpected bruising in around 15% of cases

• Lethargy, low energy and weakness, in 15% of cases

• Not eating in 14% of cases

• Weight loss in 11% of cases

• Seizures, resulting from bleeding in the brain

• Collapse and shock

Which dogs are most likely to get lungworm?

Worming

• Dogs who don't get a regular prescription wormer effective against Angiostrongylus

Geographical Location - Where you live

• Slugs infected with Angiostrongylus larvae are most common in certain parts of the UK

• Large numbers of infected foxes live in the South East of the UK

• You can check the prevalence where you live on the Elanco lungworm map

Age

• Young dogs, more likely to be curious about slugs and snails

• Dogs under 2 years old are 4 times more likely to get Angiostrongylus lungworm

Breed

• Although any dog can get lungworm, purebred dogs are reported to be 20 times more likely to develop lungworm than cross-breeds

• Cocker Spaniels and Cavalier King Charles Spaniels seem to be more susceptible

• Staffordshire Bull Terriers seem less at-risk

Lifestyle: The average UK garden has 20000 slugs, increasing the risks for:

• Dogs who spend a lot of unsupervised time in their garden

• Dogs whose toys are left out in the garden overnight

• Dogs who are fed outside

Are infected dogs a risk to other pets and people?

• Infected dogs shed Angiostrongylus larvae into the environment. Where slugs are also present, this increases infection risks for other dogs in the household/neighbourhood

• Humans don’t catch Angiostrongylus lungworm from dogs

How do vets diagnose Lungworm in dogs?

Lungworm in dogs can be difficult to recognise and diagnose. There’s a wide range of symptoms. These symptoms can also be caused by other common illnesses.

Diagnosis is based on:

• Symptoms and known risks

• Blood tests: The IDEXX Angio Detect Test gives results in minutes

• Faecal tests: looking for Angiostrongylus eggs or larvae

• Chest x-rays

• Bronchoscopy: passing a special camera along the windpipe to look at the airways

How do vets treat Lungworm in dogs?

Treatment for lungworm in dogs depends on the symptoms and their severity. If your dog is diagnosed and treated early, their outlook is likely to be good. Dogs who develop severe symptoms, such as breathing difficulties and seizures, have a poor outlook and, sadly, may not survive.

Mild infections: coughing

• Medicine to kill the parasite: granules, liquid, paste or tablets

• Careful monitoring: killing lots of worms at once can trigger a severe allergic reaction and collapse

Severe infections: coughing, anaemia, collapse

• Emergency hospital treatment

• Oxygen: when lungworms cause severe lung damage

• Fluid therapy: life-saving fluids given directly into a vein in your dog’s leg

• Blood transfusion: to replace your dog’s red blood cells and help their blood to clot

• Other medications: depending on your dog’s symptoms. For example, anti-seizure medication

How to look after a dog with Lungworm at home

There are no home remedies for Lungworm. Affected dogs need prompt veterinary care and prescription medicine.

If you see your dog come into contact with a slug or snail, or licking slug slime:

• Wash their mouth out thoroughly

• Clean their teeth

• Contact your vet to get a prescription wormer effective against Angiostrongylus

After seeing a vet:

• Give all prescribed medicines at the correct time and dose

• Complete the course of treatment

• Keep recovering dogs calm and let them rest

• Keep your dog cool in a well-ventilated room

How to prevent Lungworm in dogs

Preventing lungworm is much easier than treating it. Across-the-counter wormers won't treat Lungworm.

• Use regular, monthly preventive treatments: ask your vet for a suitable prescription wormer

• Regular treatment prevents further spreading of the parasite in the environment

• Don't feed your dog outside

• Avoid leaving food bowls and toys outside, and wash them daily to remove any slug slime

• Try to prevent your dog from eating snails or slugs in your garden or on walks

• Walk your dog on the lead in the mornings and evenings and in damp weather, when they’re more likely to come across slugs and snails

When to worry about Lungworm in your dog

Contact your nearest vet if your dog:

• Is having difficulty breathing

• Develops weakness, pale gums, bleeding in the white parts of their eyes

• Has seizures after being unwell

• Collapses

Joii can help with:

• Choosing the right wormer for your dog

• Understanding risks of worms

• Keeping your dog healthy with regular preventive care