This post is sponsored by Elanco. For more information, visit their useful local Lungworm map here!

Lungworm is a real threat to our dogs. Easy for them to catch, easy for us to miss, potentially fatal, and getting more and more common in the UK. But what can we do about it? What are the options to protect our pets?

1) Prevention is better than cure

Once a dog is infected with Angiostrongylus (the most important type of lungworm), the damage to their body starts to mount up. Coughing, difficulty breathing, and damage to heart function are all common and often surprisingly subtle. However, they can also be difficult to reverse once well established. Once there is a severe parasite burden, even rapid treatment to kill the worms can in fact make breathing more difficult and cause more inflammation within the lungs, as well as a massive build up of fluid within the abdomen (ascites). If untreated, infection will usually not resolve on its own.

Even more importantly, the presence of the parasites in the bloodstream often causes a “coagulopathy”; alterations to the blood’s clotting ability. This results in abnormal bleeding – for example, bruising – that is initially hard to see on a furry pet. But if not very rapidly treated, this tends to progress to anaemia (1). Potentially then to severe internal bleeding (2)(3) which may be fatal without treatment.

Waiting until you know your dog has an active infection before you treat is potentially very dangerous. These dogs are often clinically unstable and treatment may be too little, too late. Or may even worsen matters in a critical patient.

2) Use prescription medicines that are effective against lungworm

The vast majority of wormers on the market are ineffective against lungworm. There are only a tiny handful of tablets and spot-ons that are effective against the parasite; some are more effective as a preventative, while others will both prevent and treat. However, all of these products are prescription-only. There are no over-the-counter medications that will reliably prevent or treat lungworm infestations. 

If you see someone marketing a product for sale in the UK that claims to be effective without prescription, they are lying – and are breaking the law. These products may not be what they claim to be, and are often dangerous to the pets they are supposed to help. Please report them to the VMD for illegal advertising and/or illegal sale! 

Remember too that none of the licensed treatments (those that are studied and are proven to be effective and safe) will last more than a month against lungworm. So whatever option you and your vet choose, make sure you administer the dose every month.

3) Minimise your dog’s exposure to the lungworm larvae

Lungworms are spread primarily by slugs and snails, and in their slime. So by preventing your dog having contact with these creatures and their trails, you do reduce the risk of infection. Key points to consider are…

  • Do you leave toys or bowls outside? If so, slugs and snails might crawl over them – so bring them in at dusk as the slugs start slithering around!
  • Do you feed your dog outside? If so, make sure that there’s no leftover food that might attract hungry slugs and snails, spreading slime and maybe lungworm larvae everywhere they go.
  • Pick up fox and dog poo – help to break the cycle of infection, protecting the slugs and snails as well as your pet!
  • Consider not encouraging foxes into your garden – many foxes carry lungworm and risk infecting your local slug population.

4) If you aren’t treating, test regularly

It might be that you and your vet plan out a personalised parasite control programme for your dog that doesn’t cover for lungworm – maybe you’re in a low risk area, or maybe there are other parasites that are higher risk that need to be focussed on. Whatever the reason, if you’re not treating regularly (especially in a high-risk area), consider talking to your vet about regular testing for lungworm. That way, you can pick up on infections early, before they cause severe disease. There are now simple blood tests that are very sensitive, and will give you an indication of infection, and allow your vet to change the control plan enough to treat for Angiostrongylus if needed.

Is your dog protected?

Follow the four steps above to give them the best possible chance: prevent, don’t wait to treat; use a suitable and safe medication; remove slug and snail attractants; and test if you can’t treat. And above all, talk to your vet, especially if your local area is at high risk (red or amber) for lungworm on the Interactive Lungworm Map!

Scientific articles:

  1. Cury MC, Lima WS, Guimarães MP, Carvalho MG (2002) Hematological and coagulation profiles in dogs experimentally infected with Angiostrongylus vasorum, Veterinary Parasitology, Volume 104, Issue 2,
  2. Willesen, J., Bjornvad, C. & Koch, J. (2008) Acute haemoabdomen associated with Angiostrongylus vasorum infection in a dog: a case report. Ir Vet J 61, 591. 
  3. Garosi, L.S., Platt, S.R., McConnell, J.F., Wray, J.D. and Smith, K.C. (2005), Intracranial haemorrhage associated with Angiostrongylus vasorum infection in three dogs. Journal of Small Animal Practice, 46: 93-99. 

Promomats Code: EM-UK-21-0050