Blue Cross animal hospitals regularly treat dogs suffering form the common disease ‘lungworm’. Caroline Reay, chief vet at the charity’s hospital in Merton, South London, explains more about this potentially fatal disease: “There are several different species of lungworm which infect dogs but the one of most concern is Angiostrongylus vasorum. This has always been present in the UK, but was only in the extreme south of England. Perhaps because of climate change, infection has recently spread northwards, even to Scotland, and become more common all across the UK.

Dogs get lungworm by eating snails, slugs or frogs, and lungworm larvae are not infective until they have grown for a few days within these animals (known as “intermediate hosts”). Lungworm cannot spread directly from dog to dog.

However, an infected dog suggests that there are contaminated slugs or snails in the local area. Other slugs and snails in the vicinity may then eat larvae excreted by infected dogs and become carriers themselves – ready to infect other dogs. Therefore just one dog with the disease increases the chance of another dog in the area contracting lungworm. Adult worms live in the heart and blood vessels of the dog. This alone can cause heart disease or pneumonia but the potential for serious illness increases from 28 days post infection, when the adult worms start to produce larvae. This may cause haemorrhages, often in the lungs, but because their presence interferes with blood clotting, haemorrhages can happen anywhere - eyes, spinal cord, intestine and liver are just some of the reported locations.

Signs of illness vary but coughing, breathing difficulties and a reduced tolerance for exercise are common. At The Blue Cross we have also seen several dogs where clotting has caused persistent (over several days) bleeding from a tiny wound, such as a torn nail.

Diagnosis isn’t always easy. The larvae can be detected on microscopic examination of faeces, but they are not necessarily present every day in all cases. There is one licensed treatment (Advocate) in the UK, which is effective in about 90% of cases.

Talk to your vet about regular treatment and prevention to keep your dog safe."

For more pet care advice visit www.bluecross.org.uk