What is lungworm?


As we enter summer and enjoy the improved weather, as vets our minds turn not to sunshine and holidays but to the delightful topic of parasites! Lungworm was historically known in ‘hot spots’ in the south of England but is now found in dogs across most of the UK. News reports about the dangers can be very worrying for pet owners, so we’ve asked our vet team for the key facts you need to know and what to do if you have a concern about your dog’s health.

What is lungworm?
Lungworm is a type of parasitic worm that inhabits the heart and blood vessels supplying the lungs of dogs, potentially causing serious problems. The good news is that it is treatable in the earlier stages and easy to prevent with regular worming medication from your vet.

How do dogs get lungworm?
Dogs become infected by ingesting lungworm larvae. These are found in slugs and snails, including in their slimy coating. The larvae can survive for a short time away from their host and therefore can also be found in the environment out on walks, on outside water bowls and on dog toys left outside in areas where slugs and snails frequent and leave their slime trails behind.

The life cycle of the lungworm requires a slug or snail host so while dog-to-dog transmission is not possible, larvae shed in the faeces of infected dogs infects further hosts and continues the spread of the parasite.
Not every slug and snail carries the larvae but habitual slug and snail eaters are considered most at risk of exposure.

What are the signs and symptoms of lungworm in dogs?
Prevention is key as infected dogs may show no symptoms at all or only vague signs which are easily mistaken for other common health problems. Any change in your pet’s health or behaviour should be checked out by your vet as soon as possible.

The most common sign is coughing. Other symptoms can include lethargy, shortness of breath, weight loss, pale gums, unexplained bruising and bleeding.

Left untreated the parasite can cause progressive heart and lung disease and fatal haemorrhage.

Diagnosis can be difficult as it relies on finding evidence of the worm. Your vet may use a variety of methods – blood sampling, bronchoscopy (using a tiny camera to examine the airway), chest x-rays and looking for larvae in a dog’s faeces. Not finding the worms does not necessarily mean the dog is not infected so treatment sometimes begins based on history, clinical signs and response to the treatment. 

This involves a course of anti-parasitic (worming) medication.

We recommend that lungworm prevention medications form part of your regular worming routine. It’s a common misconception that all worming medications treat every type of worm, so it’s best to speak with a vet or nurse to make sure your dog is on the most appropriate programme for their age and lifestyle. 

Members of our Healthy Pet Club can receive this treatment as part of their health plan.

Preventing young, inquisitive dogs from eating slugs and snails is easier said than done but if you catch them sniffing at one, move them away from the danger zone immediately. Picking up your dog’s faeces promptly and removing toys and water bowls from the garden overnight can help to reduce the risk of transmission.

Dr Carlie McMillan BSc BVMedSci BVM BVS GPCert (FelP) MRCVS

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