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Is your dog at risk from lungworm?

Intro Text
How the parasite that might be lurking in your garden could pose a serious health risk to your dog.

Slugs and snails can be a real threat to your dog if they are carrying potentially fatal lungworm larvae. Make sure you know how to spot the warning signs.
Young boy plays with dog in garden

What is lungworm?
The lungworm (Angiostrongylus vasorum) is a parasite that can cause serious health problems in dogs and can even be fatal if not diagnosed and treated promptly. Lungworm has spread considerably in recent years and is now endemic in much of the UK. A survey by researchers at the Royal Veterinary College in London found that one in five veterinary practices in the UK has reported at least one clinical case in a dog.1 You can see whether cases have been reported in your area by visiting the lungworm map. You can also use the map to report your own dog’s lungworm infection, alerting other local dog owners to the risk.

How do dogs get lungworm?
Lungworm larvae are carried by slugs and snails and can be picked up by dogs if they deliberately or accidentally eat these common garden pests whilst rummaging through undergrowth, drinking from puddles, eating grass, or playing with toys that have tiny slugs or snails stuck to them. It’s even been shown that the larvae are released into the mollusc’s slime, making this another possible source of infection.2 Once a dog is infected it will expel lungworm larvae in its poo, and slugs and snails become infected when they come into contact with that poo. Foxes can also become infected with lungworm, and play a part in spreading the parasite around the country. With more people travelling in the UK with their pets, and foxes roaming up to fifty kilometres, there is a very real risk that this parasite will continue to spread around the country. Frogs can also carry the larvae, posing an additional risk to dogs.

Is my dog at risk?
Dogs of all ages and breeds can become infected, but younger dogs seem to be more prone to picking up lungworm. Dogs who are known to eat slugs and snails are also considered at high risk, but remember slugs and snails can be tiny and you may have no idea that your dog has eaten one.

Where does lungworm live in my dog?
When a dog eats an infected slug or snail the lungworm larvae are released into the dog’s intestines. From there the larvae burrow through the gut wall and make their way towards the heart, where they develop into adult worms and reproduce. Lungworm eggs are carried in the bloodstream to the lungs, where they hatch into new larvae that burrow through the lung tissue. These larvae are coughed up by the dog, swallowed and then pass out in the dog’s poo, ready to infect more slugs and snails to continue the cycle.

What risks does lungworm pose?
Lungworm can cause a range of symptoms that can often initially be confused with other illnesses. Breathing problems including a cough are common signs, but not all dogs with lungworm will cough, so you can’t rule it out just because your dog hasn’t got a cough. Other potentially serious symptoms include abnormal bleeding and neurological problems, as well as more general signs like lethargy, depression, vomiting and diarrhoea. Of course, all of these symptoms can be caused by other diseases as well, which can make diagnosis tricky. The parasite can be fatal if left untreated, so it’s important to get your dog checked over by a vet if you have any concerns.

How do I know if my dog has lungworm?
The signs of lungworm can be easily confused with other illnesses, so it is important to consult your vet immediately if your pet displays any of the following:

  • Changes in behaviour – depression, lethargy or seizures
  • Breathing problems – coughing or tiring easily
  • General sickness – weight loss, poor appetite, vomiting or diarrhoea
  • Poor blood clotting – for example excessive bleeding from minor wounds, nose bleeds, bleeding into the eyes or paleness around the eyes and gums indicating possible anaemia

Dogs can show just one of these symptoms, or a combination of them.

How do I prevent my dog from getting lungworm?
If spotted and treated early enough most dogs will make a full recovery, but as this parasite can be fatal, the best way to ensure your pet is protected is by regularly using a product that acts as a preventative. However, not all wormers are effective against lungworm so be sure to ask your vet for advice. Remember, for lungworm prevention must be monthly; using a product every 3 months will not prevent this potentially fatal parasite, as this leaves the dog unprotected for too long between doses.

Did you know…
The average UK garden is thought to contain more than 20,000 snails and slugs3, any one of which could be carrying lungworm larvae.

Ask your vet about a lungworm prevention plan.

1 Kirk et al., Vet Record (2014), 175, 118

2 Conboy G et al., Parasitol Res (2017), 116: S41-S54