Wondering how to spot fleas, worms or ticks on your dog or cat. You’ve come to the right place.

Even the cleanest and most well-cared-for pets can pick up parasites.

The most common places pets come into contact with parasites are our gardens and outside spaces, rather than direct contact with other animals.

95% of fleas live in carpets, floorboards and soft furnishings

You’re unlikely to see the parasites themselves but you may see evidence of them on your pet’s skin, in your home or changes in your pet’s behaviour. Although parasites are often invisible to us, fleas, ticks and worms can affect our pets’ health – and our own health too.

Zoonosis is a technical term for an infectious disease which can be transmitted from animals to humans. There are a number of different zoonoses all around us, including some parasites that pets can carry.

Preventing Parasites

Routinely treat pets fleas to make sure any fleas pets pick up don’t survive for long enough to become established in our homes

Worm your pet regularly to reduce the number of worm eggs being shed into the environment.

Vacuum regularly and thoroughly, especially below curtains, under furniture edges and where pets sleep as it’s estimated that vacuuming can remove up to 50% of flea eggs. Treating your home with a household flea spray will prevent flea eggs from developing in your home.

Clean up pet faeces regularly to reduce environmental contamination with infective parasite stages.

Reduce the temptation for rodents to come into gardens and spread parasites by keeping them clear of rubbish and food waste.

Muddy shoes and wheels can harbour parasite eggs so keep them clean too.

Always wash pet bedding on hot washes 60°C+.

Always wash your hands after gardening as soil can be contaminated by worm eggs.

Ask your vet how to approach a year round Zero Tolerance to parasites


Dog with fleas and ticks

Fleas are the most common visible parasite affecting cats and dogs. They are a year-round problem and can also transmit tapeworms to your pets. If uncontrolled, flea numbers can grow rapidly.

It is important to treat both your home and your pet, ask your vet for advice.

1 flea can become 1,000 in just 21 days

The most common flea we see can survive on both dogs and cats – but luckily not humans.

Fleas are hard to spot so just because you’ve not seen one on your pet, it doesn’t mean that they’re not there.

Irritating to humans and pets, fleas feed on the blood of their host and can be a trigger for allergic skin disease. This can lead to redness, itching, pain and infection, particularly at the base of the tail, groin area and along the stomach.

Fleas can survive both within our homes and in the outdoors environment so a year-round prevention regime is vital.

Some species of flea can jump more than 200 times their height. That’ equivalent to an adult human being capabl of jumping over the Eiffel Tower!

Cat itching from fleas

How do fleas affect people?

Fleas can occasionally bite people causing localised itching, redness and soreness. The most common site for bites is around the feet and legs, these being the most accessible parts available to newly hatched fleas as they emerge from a pupae lodged in the carpet.

Cat Scratch Fever is a bacterial zoonotic disease carried by fleas and can be found in around 40% of cats at some point in their lives? People with weak immune systems are at increased risk of getting seriously ill with cat scratch fever. The key to preventing cat scratch fever is to practise excellent flea control and avoid cat scratches or bites.


Although we might not often see these parasites, they’re all around us, including in parks and public play areas. Some worms can infect humans and cause serious disease – accidental ingestion of roundworm eggs from contaminated soil can even, in rare cases, result in blindness.

Protecting your pet, family and home

Worms of dogs and cats in the UK are transmitted by contaminated faeces – hygiene is fundamentally important when preventing infection, particularly washing hands after handling pets and gardening, and before eating food.

Adult ringworms can grow up to 7 inches long

Try to minimise exposure, especially of children, to potentially contaminated environments.

Cleaning up faeces is crucial to reduce the number of worm eggs in the environment, but even the most diligent hygiene cannot fully protect dogs and cats from infection. Worm eggs are abundant in the environment due to their hardy exterior and long life.


Diagram of different types of lungworm for Dogs

Lungworm can be a very serious disease affecting dogs.

Dogs can be infected with lungworm when they eat a slug, snail or frog infected with lungworm larvae. Once in the stomach the larvae migrate to the airways, blood vessels and the heart.

Adult worms lay eggs that develop into tiny larvae and are coughed up and swallowed. Larvae pass out in the faeces where they enter slugs and snails, starting the cycle again.

The parasites can cause damage to blood vessels and airways. Common signs include a cough, breathlessness or breathing difficulties but can include weight loss, lethargy, reduced appetite, anaemia and abnormal bleeding.

Dogs of all ages and breeds can become infected but younger dogs seem to be more prone to picking up the parasite because of their curiosity. Dogs can’t pass the infection directly to one another – it’s important to try to stop them eating slugs, snails and frogs, and to use regular treatments from your vet to protect your dog.

If you’re concerned, it’s always best to take your pet to the vet to be checked. If caught early enough, treatment for lungworm is usually successful.


Fleas and chewing lice can transmit tapeworms. Tapeworms use their sharp teeth to attach themselves to cats’ and dogs’ gut walls.

They can grow to around half a metre in length inside the guts. Segments packed with eggs, break off and are excreted in the faeces looking like grains of rice.

Most tapeworms found in the UK rarely cause any symptoms, but can deprive your pet of vital nutrients. Some tapeworms found abroad can be a significant risk to human and pet health. It’s always important to discuss parasites with your vet before you travel.


Pets of any age can become infected with roundworms by picking up worm eggs and larvae from the soil, ingesting faecal matter, hunting rodents and by feeding or scavenging on raw meat or carcasses.

Puppies can become infected while in the mother’s womb if the mother is already infected, and both puppies and kittens can become infected through the mother’s milk.

Symptoms in infected cats and dogs can include loss of condition, lethargy, weight loss, anal irritation, diarrhoea and respiratory problems. In puppies and kittens, a heavy worm burden can also cause intestinal blockage with possible life-threatening consequences. Some roundworms can be zoonotic, so cleaning up faeces is a crucial part of responsible pet ownership.


5 common places ticks hide on dogs

Ticks are external parasites, which feed on the blood of animals and humans. They cannot fly or jump but use their eight legs to crawl into undergrowth and climb up long grasses from which they can fall on pets.

They can range in size from a pinhead, up to around the size of a fingernail when fully swollen and engorged with blood.