Worming and flea treatment

Regular, year-round flea and worm control is an integral part of taking good care of your pet’s health. Some of the parasitic diseases are zoonotic, which means, that they can be transmitted from pets to humans.

During our home visit service, we provide the following:

  • Education on how to safeguard your pet and your home from worm and flea infestation
  • Expert advice to help find the product that’s right for you and your pet’s lifestyle.

As the majority of products we sell are prescription-only medicines, we need to have seen your pet in the last 12 months to legally dispense flea and worming treatment.

Please be aware that many products available over the counter often aren’t as effective and might not cover all the species of internal and external parasites your pet could get.

It is also crucial to know that parasite treatments are only given to the pet they have been prescribed for, as certain products can be fatal to other species.

Even if you cannot see any evidence of parasites your pet could still be infected. Therefore regular, year-round flea and worm control are recommended.

What sort of external and internal parasites affects dogs and cats?

Dogs and cats frequently pick up external parasites (ectoparasites) such as , fleas, lice, ticks and mites.

There are various internal parasites (endoparasites) that can infect your pets and pose a threat to your family. Worms that target pets include lungworms, roundworms, tapeworms, whipworms, hookworms.


Flea bug
  • Dogs, cats and rabbits pick up fleas from infested environments such as your garden or parks, where untreated pets or wildlife such as foxes, birds, hedgehogs and rodents have been.
  • Fleas, and especially the cat flea, are not host-specific and can feed on most mammals, including humans.
  • Climate is an important factor for flea infestations. During the colder months, fleas lay fewer eggs and their lifecycle takes longer to complete and opposite from spring to autumn when eggs can develop into new fleas within just 14 days.
  • Only 5% of the flea infestation is on your pet and 95% of the problem is actually in the environment (carpet, furniture and pet’s bedding).
Flea cycle
  • Fleas begin feeding immediately after acquiring a host and excrete “flea dirt” as a food source for larvae.
  • Female flea is 4mm long and male flea is 2 – 3mm long
  • Only 24 - 48 hours after mating on the animal, females can start laying eggs and each female can deposit 30 - 50 eggs per day.
  • Just 5 fleas on an untreated pet could lead to more than 1,000,000 eggs being laid in only four weeks!
  • Eggs may hatch into larvae on the pet or can fall off anywhere in the environment along with skin cells and flea dirt (flea feces).
  • Flea larvae look like tiny maggots and they hate the light so will crawl away to hide in the darkest crevices of the home, burrowing into carpets and cracks in flooring, hiding under cushions and sofas.
  • The larvae feed on organic debris (skin cells and flea dirt) found in their environment.
  • Flea larvae undergo 3 stages (L1 – L2 – L3) which last for 1 – 2 weeks and then spin silk-like protective cocoon and become a pupae.
  • There is no chemical product that can kill the cocoons (pupae).
  • Pupae can remain dormant for over a year but may hatch in as little as 5 - 8 days under ideal environmental conditions (i.e. temperature, humidity and presence of host).
  • Flea pupae can sense movement, warmth and even the breath of a passing host, which will stimulate them to rapidly emerge from the cocoon, and jump onto a host ready to have their first meal, and start breeding and laying eggs.
  • Female fleas ingest 15 times their own weight in blood per day.
  • Fleas will make your pet itch and scratch and can also be quite sneaky, hiding deep in the fur. Often the only evidence of a flea infestation seen is the ‘flea dirt’ they leave behind.
  • Fleas are a major cause of skin disease and flea bites can irritate your pet‘s skin and provoke an allergy (Flea Allergy Dermatitis).
  • Flea act as intermediate host for one type of tapeworm (Dipylidium caninum).
  • If you see fleas on your dog or cat you should treat the entire house and other areas your pet may go with a household flea spray.
  • Use household flea spray on soft upholstered furniture, carpets and flooring, pet bedding and surrounding area including the car, to fight fleas, and their immature life stages.
  • Perform mechanical removal of any eggs and larvae, by regularly washing the pet’s bedding at 60C and vacuuming all floors and soft furnishing.
  • Comb your pets regularly to keep an eye out for any signs of fleas: fleas themselves or flea dirt.
  • If the environment remains untreated, an infestation can continue for 3 years, even without an animal present.


There is no chemical product that can kill the cocoons (pupae) in your home, so you have to wait for them to develop into fleas and hatch out and then jump on to your treated pets for them to be killed. It can take more than 3 months to get rid of a flea home infestation because of the “pupal window”.

You should be aware that no product stops fleas from jumping onto pets, which is why it is normal to still see some fleas after treatment. In fact, fleas may become more visible. If your pet was treated with an effective product, the fleas will be killed within 24 hours of jumping onto your pet.

To prevent a flea infestation you will need to treat all pets (cats and dogs) in the household regularly (every four weeks for optimal protection). We can recommend and prescribe effective flea treatment products for your pet.


  • Lice are insects that can be seen with the naked eye. Lice are flat, small, wingless insects which fall into two categories. The sucking lice feed on blood, whilst the biting or chewing lice fed on hair and skin debris.
  • Lice are highly host specific, meaning that a dog louse will not infect a cat, and vice versa.
  • The most important lice species that affect dogs and cats are:

Felicola subrostratus, which occurs in cats worldwide. It is a rather small chewing louse, 1.2 to 1.3 mm long, i.e., it does not suck blood. It attacks mostly stray cats, but also old, neglected or otherwise weakened cats, especially longhaired breeds. It can transmit Dipylidium caninum, a parasitic tape worm of dogs and cats.

Felicola subrostratus

Felicola subrostratus

Trichodectes canis

Trichodectes canis

Trichodectes canis - infests dogs worldwide, 1.5 to 2 mm long. It is a chewing louse. It prefers the head, ears, neck and back of its hosts. It can transmit Dipylidium caninum, a parasitic tapeworm of dogs and cats.

Linognathus setosus, the dog sucking louse, occurs in dogs worldwide. It is a blood-sucking species 1.5 to 2.5 mm long. It is found often on the head (especially around the eyes and the ears), the neck and the breast of dogs.

Linognathus setosus

Linognathus setosus

  • Lice spend their entire life cycle on the pet which is about 21 days.
  • Lice eggs, called nits, are whitish, about 1 mm long and are glued to single hairs.
  • Transmission of lice is by direct contact with an infested pet. Unlike fleas and ticks, lice do not persist or travel in the environment. Grooming instruments may, however, serve as a source of transmission.
  • Very young, old or otherwise unhealthy animals are most at risk.
  • The most noted sign of a louse infestation is a scruffy, dry hair coat.
  • Damage to the skin from scratching can result in inflammation, hair loss and bacterial infection.
  • Sucking lice are vectors of several blood-borne diseases.
  • Very heavy infestations of blood-sucking lice, especially in puppies and kittens may cause anaemia.
  • A diagnosis can usually be accomplished with the naked eye. Nits tend to be more visible than the actual louse, but both can be seen.
  • Infestation with lice is now relatively uncommon as many flea treatments also destroy lice.


  • The largest ectoparasite is the tick, which can be picked up by your dog or cat wherever they go – not just in forest and grassy areas, but also in urban parks and even gardens.
  • There are 3 main species of ticks across Europe that affect pets:

Ixodes ricinus is the most common tick in the UK and Ireland (90% of ticks in the UK).

Ixodes ricinus

Dermacentor reticulates is mainly found in wooded areas across Western Europe.

However it is largely found in coastal areas within the UK (West Wales and South West England, with a recently discovered population in Essex.

Dermacentor reticulates

Dermacentor reticulates

(Adult female)

Rhipicephalus sanguineus

Rhipicephalus sanguineus

(Adult female)

Rhipicephalus sanguineus is known as the brown dog tick.

This species is non-endemic to the UK. Normally is found in Southern Europe where the climate is much warmer, but recently has been indentified occasionally in the UK on imported dogs. Although current climatic conditions in the UK are unlikely to permit the survival of this species outdoors, so indoor infestations can occur. This not only increases the risk of people and their pets being bitten, but can also result in a tick infestation in the home which requires fumigation to remove the ticks.

Rhipicephalus sanguineus can transmit Mediterranean spotted fever, canine babesiosis and ehrlichiosis.

With the increasing number of dogs travelling or being imported, it is likely that importation and infestation events in the UK will continue and may result in pathogen transmission.

  • Ticks wait on vegetation waving their forelimbs, waiting for a host to pass by.
  • They latch on to most mammals, including dogs, cats and humans, and often attach to less furry areas: face, ears, abdomen and legs.
  • Ticks have highly developed mouthparts, which allow them to pierce a hole through the skin to feed on blood for several days before dropping off from their host. Unfed, they are small as a sesame seed, but females can swell up to 200 times their size (the size of a coffee bean) when engorged.
  • They can cause reaction at the site of attachment such as infection or an abscess, so therefore should never just be pulled off.
  • Ticks may cause anaemia if there is a severe infestation in a young animal.
  • Ticks can transmit serious infectious diseases such as Lyme disease, Babesiosis and Ehrlichiosis. The longer the blood meal, the greater the risk of disease transmission.

Lime Disease

Infectious agent: Borrelia burgdorferi

Borrelia burgdorferi

Borrelia burgdorferi

Ixodes ricinus

Ixodes ricinus

Vector: Ixodes species tiks – such as Ixodes ricinus and Ixodes hexagonus (hedgehog tick) are endemic in the UK.

Affects: humans, dogs (cats rarely)

Clinical signs in dogs: dogs can develop swollen joints and stiffness also fever, anorexia and lethargy.

Symptoms in humans:

Early stage: tiredness, flu-like symptoms, muscle and joint pain, bull’s eye rash

Middle stage: numbness, localised paralysis

Late stage: chronic joint pain

Bull’s eye rash

Bull’s eye rash

Tick-borne encephalitis (TBE)

Infectious agent: Tick borne encephalitis virus (flavivirus)

Vector: Ixodes ricinus

Affects: humans and less commonly dogs

Clinical signs in humans: this disease can cause ataxia, proprioceptive deficits, seizures, tremor, paresis, paralysis and cranial nerve deficits such as facial paresis.


Infectious agent: Babesia canis

Babesia canis

Babesia canis

Vector: Dermacentor reticulatus (in UK)

Dermacentor reticulatus

Dermacentor reticulatus

Adult male

Dermacentor reticulatus

Dermacentor reticulatus

Adult female

Affects: dogs

Clinical signs in dogs: this disease destroying red blood cells and causing acute signs of anaemia (pale gums, lethargy, loss of appetite), jaundice, red/brown urine in affected dogs (but not in humans).

Babesiosis is an emerging tick-borne disease. It is mainly found in mainland Europe, but there is a risk of spread into the UK and Ireland. In 2015 – 2016 there were a few cases of Babesiosis in dogs in Essex and a population of infected ticks was identified. If you have recently been on holiday, travelled with your pet or imported an animal and have found a tick and would like to know what species it is, you can send your specimen to the TRS for identification. Email tick@phe.gov.uk, or visit www.gov.uk/tick-recording-scheme to find out more.

Adequate tick prevention is the best form of protection. Generally, the best products are those that kill the tick soon after attachment and/or have repellent activity. It is a good practice to examine your dog regularly (daily) for ticks and remove them as soon as they attach to reduce the chance of contracting diseases. Pathogen transmission only occurs after 24 hours of attachment.

How to remove a tick:

  • You can use tick removal tools or pointy tweezers.
  • Grasp the tick close to the skin. Tweezers tips should be on, or as close to the tick head as possible.
  • Pull upwards gently, with slow, steady motion, do not twist, jerk or pull hard, or you may break off the mouth part leaving it in the skin.
  • Be careful not to squeeze or crush the tick’s body as it may contain infectious organisms.
  • Wash the bite area and apply an antiseptic, then wash your hands with a disinfectant soap.
  • You can save the tick for identification in case your pet becomes ill. You can place it in a sealable plastic bag in your freezer.


These are small insects which are barely visible to the naked eye.


  • Ear mite infestation is most commonly caused by Otodectes cynotis (8-legged parasite) that live out their life cycle in your pet’s outer ear canal, feeding off skin debris, wax and oils.
  • They can infest cats, dogs, rabbits and ferrets and are highly contagious.
  • Kittens are particularly susceptible but any cat or dog in close contact with an infested pet is at risk.
  • While the mites do not actually bite your pet, the movement of these parasites in their ear canal is extremely irritating and causes dog and cat to scratch at them, often resulting in secondary fungal and bacterial infections.
  • Typically, ear mites will also cause a dry black ear discharge. There may also be an unusual odour.
  • The mite is barely visible to the naked eye and may be seen as a white speck moving against a dark background.
Otodectes cynotis

Otodectes cynotis

We will advise you about which insecticidal products are suitable. There are several ear medications licensed for the treatment of ear mites in pets. No medication can penetrate the eggs or pupae, so treatment is directed at killing the adult and larval forms.


  • Demodectic mange is caused by Demodex canis, a parasitic mite that lives in the hair follicles of dogs.
  • Under the microscope, this mite is shaped like a cigar with eight legs.
Demodex canis

Demodex canis

  • Demodectic mange, sometimes just called ‘demodex’ or ‘red mange’, is the most common form of mange in dogs.
  • All normal dogs (and many humans) have a few of these mites on their skin. As long as the body's immune system is functioning properly, these mites cause no harm.
  • This disease occurs primarily in dogs less than 12 to 18 months of age. As the dog matures, its immune system also matures.
  • Demodectic mange may occur in older dogs because the function of the immune system often declines with age. Dogs whose immune system is weakened due to illness or certain medications are also susceptible to demodectic mange.
  • Demodectic mange is not contagious to other animals or humans.
  • Demodex mites are transmitted to puppies from their mother during the first few days of life. Since the mite is found on virtually all dogs, exposure of a normal dog to one with demodectic mange is not dangerous, as the immune system must be depressed for mange to develop.
  • Because the disease is due to a genetic defect, affected dogs should not be bred, and the parents of the affected dog should not be bred again.
  • Surprisingly, a dog with demodectic mange usually does not itch severely, even though it loses hair in patches. The hair loss usually begins on the face, especially around the eyes. When there are only a few patches of hair loss, the condition is called localized demodectic mange. If the disease spreads to many areas of the skin, the condition is called generalized demodectic mange.
  • We can take deep skin scrapings and examine them under the microscope to diagnose this disease. The finding of larger than normal numbers of Demodex mites in skin scrapings confirms the diagnosis.
  • Treatment of demodectic mange is generally successful. However, if the immune system is weakened, neither the mites nor the infection may respond to treatment. With generalized demodicosis, successful treatment may take a long time and may require regular skin scrapings to check the progress of the treatment.
  • Because the immune system does not mature until 12 to 18 months of age, a dog with demodectic mange may have relapses until that age. In addition, dogs with suppressed immune systems may be susceptible to relapse. It is important to treat as soon as a relapse occurs to minimize the possibility of developing uncontrollable problems. Relapses are usually recognized 3-6 months after treatment is discontinued.


  • Sarcoptic mange (canine scabies) is caused by the burrowing mite Sarcoptes scabiei and is carried by foxes.
Sarcoptes scabiei

Sarcoptes scabiei

  • Female mites burrow just below the surface of the skin forming tunnels where the eggs are laid and larvae and nymphs grow.
  • Mites cause an intense inflammatory reaction, itching, and self-trauma. Secondary bacterial infections are common.


  • The Cheyletiella mite is an uncommon but highly contagious zoonotic skin parasite. Affect dogs, cats, rabbits and humans.

Dogs: Cheyletiella yasgury

Cheyletiella yasgury

Cheyletiella yasgury

Cats: Cheyletiella blakei

Rabbits: Cheyletiella parasitovorax and Cheyletiella firmani

The mites do not have much host specificity. They can also affect humans in contact with the infested animal. Human infestations usually resolve in 3 weeks if the host animal is treated.

  • During their life cycle the mite goes through 4 stages: egg, larva, nymph, and adult.
  • The entire life cycle is completed on the host in 21 days.
  • Cheyletiella mites spend most of the time in hairs and go to the skin surface to feed on epithelial debris. The mites move around under the scales of a dog’s skin, creating an appearance of dandruff that is actually alive and moving “walking dandruff”.
  • The scaling and itching are most common over the backs of pets, but can be located anywhere on the body. Due to self-trauma, pets may have secondary crusting in these regions.
  • Puppies tend to be more prone to cheyletiellosis, especially those from places where there are lots of animals, such as puppy farms, boarding kennels.


  • The harvest mite, Trombicula automnalis is a small orange coloured mite that can cause skin irritation of dog, cats and other animals.
  • It differs from other mites in that only the larvae are parasitic.
Trombicula automnalis

Trombicula automnalis

  • These mites do not suck on blood or bite but feed on dead skin cells. They can however cause severe irritation and itching, possibly due to the fact that they produce and excrete a digestive enzyme to break down the skin cells.
  • The adult mite lives in the soil, whereas in late summer, the red and orange larvae attach themselves to the host and feed for 7 – 10 days before falling off.
  • The skin between the toes is a favourite site.


  • Canine angiostrongylosis is a serious life threatening disease which appears to be steadily increasing in frequency and becoming more widespread across UK.
  • It is coused by Angiostrongylus vasorum (French heartworm or canine lungworm).
Dog and snail
  • Dogs catch lungworm by eating infected slugs and snails as intermediate host or frogs or possibly birds acting as paratenic hosts. Ingested larvae migrate through liver venous circulation and right ventricle of the heart into the lungs where they mature into adults.
  • Female worms begin to produce eggs from 38-60 days after infection (pre-patency).
  • Eggs hatch into larvae in the pulmonary capillaries and then penetrate the alveoli. These larvae get coughed up and swallowed, then are excreted through the faeces into the environment. Snails, slugs and frogs can become infected if they swallow the larvae and so the cycle continues. The red foxes are natural host for lungworm so their faeces can also be responsible for the spread of the disease.
  • Lungworm infestation can lead to breathing problems, coughing or becoming tired from exercise quicker. Lungworm can also interfere with blood clotting. This can cause prolonged bleeding from small wounds, the dog having nose bleeds, bleeding into the eyes and anaemia (low red blood cells) which shows as pale membranes in the eyes and gums. This inability to clot the blood can cause major problems if an affected dog underwent surgery such as neutering. Bleeding into the brain can cause seizures and behavioural change. Less specific signs include weight loss, poor appetite, vomiting and diarrhoea. In rare cases sudden death may occur.
  • Occasionally, larvae and rarely adult stages of A. vasorum are located in ectopic locations such as the bladder, kidneys, brain or anterior chamber of the eye.
Angiostrongylus vasorum in the anterior chamber of the left eye of a dog

Angiostrongylus vasorum in the anterior chamber of the left eye of a dog

  • You should seek veterinary advice if you see any of these clinical signs. Dogs infected with lungworm can make a complete recovery if the condition is treated quickly, including the use of special worming medicines.
  • Your dog may need intensive care in the veterinary hospital if severe lungworm infections occur.
  • Prevention of lungworm is simple. A chemical spot-on product, applied monthly to the back of the neck, can prevent your dog from getting the disease by killing any larvae they pick up. This is a prescription-only product so is only available from vets.


  • Crenosoma vulpis infection shows the same lifecycle but produces a mild inflammatory response presenting as a productive cough.


  • Aelurostrongylus abstrusus in the cat follows a relatively similar lifecycle with birds and rodents as intermediate hosts, which means that cats are at risk of picking up feline lungworm when they hunt.
  • Cats can get lungworm by eating infective lungworm larvae, which can be found in the slimy coating of slugs and snails. Larvae can also be found in water bowls where slug or snail contamination might not be obvious.
  • Kittens can get lungworm from their parents, and can be infected before being born, or through the milk.
  • Usually lungworm in cats is not a life-threatening condition. But if your cat’s immune system is not up to the task of putting up a good fight against this parasite, the infection can turn out to be more serious than normally expected.
  • Lungworm in kittens can be particularly dangerous as well if your cat is a senior or there are pre-existing conditions likely to have weakened the cat’s immune system.
  • The presence of the adult worms in the airways can provoke an intense inflammatory response causing significant respiratory disease.
  • The feline lungworm Aelurostrongylus abstrusus cannot be transmitted to humans.


  • Capillaria aerophila is a rare lungworm.
  • Can infect humans but this is very uncommon.

What are roundworms and how do dogs and cats catch them?

Roundworms (also known as nematodes or ascarids) are the most common parasites in cats and dogs. As their name suggests they are round (like strings).

  • Toxocara canis and Toxascaris leonina are two important species of roundworms in dogs. Dog roundworms can grow up to 15 cm long and are white in colour.
  • Toxocara cati and Toxascara leonina are infecting cats . Cat roundworms are white to brownish-yellow, and can grow up to 10 cm long.

Toxocara canis and Toxocara cati cause more significant diseases and also may be transmitted to humans.

Toxocara cati

Toxocara cati

Roundworm Life Cycle in Adult Dogs

  • Adult male and female worms mate in the pet’s intestine. The female worm will then produce eggs, which are shed in the feces into the environment. For example a single female Toxocara canis can produce 12,500 eggs per day. These eggs mature for up to a month and then become infectious.
  • When infective eggs are swallowed by a suitable host, whether it is a definitive dog or cat host or accidental human host, the larvae will hatch and penetrate the intestinal wall and travel via the blood to the liver and then to the lungs, where they will literally burst into the alveoli and take tracheal(hepato-tracheal migration) or somatic migration.
Toxocara canis hatching process

Tracheal migration: Larvae that ascend the trachea are coughed up and swallowed. Once swallowed, they travel to the small intestine, where they mature into adults and reproduce. This hepato-tracheal migration is most common in young animals (under 6 months of age).

Somatic migration: Larvae that re-enter the alveolar blood vessels travel to the skeletal muscles or organs, where they may form cysts and their development is arrested. This can happen when the pup's immune system matures (usually by 6 months of age). Larvae can remain encysted in the dog’s tissues for months, years or even for the life time. Very few roundworms can mature into adults in the bowel of the dog. As a result, very few eggs are passed in the stool leading to difficulty in diagnosis.

In an intact female dog, encysted Toxocara canis larvae can resume development after estrus (heat), and she can shed eggs in the stool at that time. With dogs that have been spayed, development of a roundworm infection may indicate that there is an underlying immune system disease that has allowed the encysted larvae to complete their life cycle.

In humans, this migration pathway is also followed and results in the condition known as larva migrans.

Roundworm transfer to humans

Toxascara leonina is far less common, and is more often seen in older dogs and cats. Migration is restricted to the intestinal wall so that neither prenatal (in the womb) nor transmammary (via the milk) transmission occur.

Roundworm Life Cycle in Puppies

  • Puppies and kittens are infected more commonly than adult dogs and cats. Immature worms (larvae) can be passed from a mother to her developing puppies, whilst they are still in the womb (transplacental route) or via the milk (transmammary route).

Transplacental route: As mentioned earlier, after somatic migration, worms become encysted in tissues and their development is arrested. However, if a dog with encysted larvae becomes pregnant, these larvae become reactivated and travel via the umbilical vein to the in utero puppies’ liver and lungs. At the time of birth, when the puppies’ lungs inflate, the larvae then burst out and travel to the intestines via tracheal migration, where they mature in approximately 2.5 - 3 weeks. Adult ascarids that migrate to the stomach may cause irritation of the gastric mucosa which results in vomiting worms.

Transmammary route: Although the transplacental route is considered the primary route of roundworm transmission to puppies, encysted larvae can reactivate and also migrate to mother’s mammary glands, so pups may also be infected via the milk. Kittens do not become infected in uterus, but they can become infected when nursing.

The most common consequence of roundworm infection in young animals is growth reduction, dull coat, increased appetite, weakness and diarrhea also coughing due to the larval migration through the lungs. In severe cases, infected puppies and kittens can have a distended abdomen or ‘pot belly’. Worms may be vomited and often voided in the feces.

Roundworm eggs can also be spread by other animals such as rodents, earthworms, cockroaches, and birds. In these animals, the roundworms are merely transported, and do not mature into adults; if dogs or most often cats eat this paratenic host (an accidental transport host), the roundworm will be able to continue its lifecycle.

Pre-patent Period and Environmental Factors

The prepatent period of T. canis varies from 2 to 4 weeks, depending on how larvae are acquired.

  • Pups infected in utero will not shed eggs before 2.5 to 3 weeks of age.
  • Worms acquired after birth from ingestion of larvated eggs from the environment will become adults and begin passing eggs into the environment approximately 4 weeks after exposure.
  • Larvae acquired via ingestion of infected vertebrate hosts (bird, rodent) may develop into adults in as little as 2 weeks.

The prepatent period of Toxascaris leonina is approximately 8 to 10 weeks.

  • Most ascarid eggs require 2 to 4 weeks in the environment to larvate and develop to the infective stage. Toxascaris leonina is the exception; eggs of Toxascaris leonina become infective as soon as 1 week after being shed.

Because of the time required, fecal material has often broken down before the eggs are infective, and thus there is often no gross evidence that the environment is contaminated with ascarid eggs. However, once present, ascarid eggs are hardy and can survive and remain infective for months or years.

Removing eggs from a contaminated environment is difficult, and common disinfectants are not effective at killing them.

Zoonotic potential: larva migrans

Roundworms are considered zoonotic parasites, meaning that they can be transmitted from animals to humans.

Toxocara canis and T. cati can infect people if they accidentally ingest infective eggs: larvae hatch and migrate to many organs. Most human infections are asymptomatic, but fever, hepatomegaly, neurological, dermatological and systemic disease may occur, resulting in condition known as visceral larval migrans. Epidemiological studies associate the presence of circulating anti-Toxocara antibodies with asthma, epilepsy and impaired brain development. Rarely, a larva may settle in the retina and impair vision, resulting in condition known as ocular larval migrans.

Children are most at risk for infection. They usually become infected from eating fecal-contaminated soil, which is often found at playgrounds, parks or public area frequented by pets.

How can I stop my dog or cat getting roundworms?

  • Regular worming treatments.
    • Puppies should be treated with appropriate anthelmintics from 14 days old. The treatment should then be repeated fortnightly until two weeks after weaning and then monthly treatments carried out up to six months of age.
    • Because prenatal infection does not occur in kittens, fortnightly treatment can begin at 3 weeks of age and be repeated fortnightly until two weeks after weaning, then monthly treatments carried out up to six months of age.
    • To prevent transmission to the puppies, pregnant bitches can be given macrocyclic lactones on the 40th and 55th day of pregnancy, or fenbendazole daily from day 40 of pregnancy continuously to 2 days post-whelping (approximately 25 days).
    • Nursing bitches and queens should be treated concurrently with the first treatment of their offspring, as they often develop patent infections at this time.
    • For adult dogs and cats, a treatment frequency of at least 4 times per year is advisable.

We will design the most appropriate deworming schedule for your pets.

  • Rodent control is important since rodents can serve as a source of infection.
  • The best environmental treatment is prevention
    • Remove your dog's feces as soon as possible to prevent the spread and transmission of roundworms.
    • Clean cat litter boxes as often as possible.
    • Practice strict hygiene particularly with children. Do not allow them to play in potentially contaminated environments and ensure proper and frequent hand washing.
    • Keeping sandpits covered when not in use is helpful in discouraging neighborhood cats from using them as litter trays and contaminating them with eggs of T. cati.


Tapeworms are helminthes belonging to the class Cestoda and are common parasites of cats and dogs. Tapeworms match their name, and look like long ribbons or pieces of tape. Unlike other intestinal parasites, dogs and cats cannot become infected by eating fertilized tapeworm eggs. Tapeworms must first pass through an intermediate host (a flea, life stock or rodents) before they can infect your pet.


  • Dipylidium caninum, is the most common type of tapeworm in cats and dogs.
  • Flea tapeworms are long, flat, white worms, and may reach a length of 50cm.
  • They are made up from individual segments called proglotids, which look like grains of rice or cucumber seeds.
Dipylidium caninum

Dipylidium caninum

Dipylidium caninum eggs

Dipylidium caninum eggs

  • Segments are shed at intervals and pass into your dog’s or cat’s feaces.
  • Fleas (Ctenocephalides spp.) and occasionally Trichodectes canis (the dog louse) act as an intermediate host for this tapeworm.
  • Flea larvae ingest the tapeworm eggs. Once inside the larval flea, the tapeworm egg continues to develop as the flea matures into an adult flea.
  • During grooming, or in response to a flea bite, a dog inadvertently ingests the tapeworm infected flea completing the lifecycle.
  • As the flea is digested, the tapeworm egg is released, it hatches, and then anchors itself to the lining of the small intestines. Here, the tapeworm is able to continue the next stage of its lifecycle, eventually maturing into a fully grown adult tapeworm.
Tapeworm Life Cycle
  • Living in the dog’s gut, tapeworms feed off the food the host animal eats, reducing the number of nutrients available.
  • Most infections with Dipylidium caninum are asymptomatic.Occasionally dogs will drag their bottoms on the ground, a behavior known as scooting, in order to calm irritation associated with the proglottids.
  • Mild gastrointestinal disturbances may occur such as vomiting or diarrhea.
  • In puppies, heavy tapeworm infestation can be more serious. Lack of growth, anemia, and intestinal blockages can occur.
  • Occasionally proglotids can be seen moving on the hairs around the anus, or more commonly, on the surface of freshly passed feces. As the segments dries, it becomes a golden color and eventually breaks open, releasing the fertilized eggs into the environment. A segment may contain as many as 20 tapeworm eggs.
  • Humans also acquire infection by ingesting the contaminated flea. Children are most frequently infected, possibly due to close contact with flea-infested pets. The infection is self-limited in humans and usually resolves spontaneously in 6 weeks.

Other tapeworms found in our UK dogs include Taenia species, and Echinococcus granulosus


Echinococcosis is a parasitic disease caused by infection with tiny tapeworms of the genus Echinococcus. Echinococcosis is classified as either cystic echinococcosis or alveolar echinococcosis.

Cystic echinococcosis , also known as hydatid disease, is caused by infection with the larval stage of Echinococcus granulosus.

Alveolar echinococcosis disease is caused by infection with the larval stage of Echinococcus multilocularis.

Echinococcus granulosus tapeworms

It is a serious zoonosis and despite extensive attempts to control it, endemic foci in the UK remain.

  • Echinococcus granulosus (dog tapeworm) is a small cestode (2 – 3mm) that inhabits the small intestine of dogs and some other canids, excluding foxes, and do not cause disease in dogs. Dogs (the final host) may become infected by eating undercooked or raw meat or viscera of infected sheep, cattle, goats, and pigs (the intermediate host).
Adult in small intestine

Adult in small intestine

  • This type of tapeworm, however, cause significant pathology in humans with large hydatid cysts developing in the liver, lungs, bone, central nervous system and heart . The only effective treatment for hydatid disease in humans is surgical removal of cysts. Hydatid disease is not contagious, and cannot be passed from person to person but it is possible that more than one family member could get hydatid disease if the family dog is infected.
Tapeworm Life Cycle
  • Humans can pick up the infection directly from infected dogs. People, especially children, become infected by ingesting eggs through hand to mouth transfer of eggs after contact with the faeces or contaminated fur of infected dogs. Eggs may also be passed when dogs lick people. It may also occur following ingestion of food, water or soil which has been contaminated by infected dog faeces. Eliminated segments of the tapeworm present in dog faeces have been reported to migrate some distance over grass or garden vegetables before expelling eggs that subsequently adhere to the vegetation. Humans are intermediate 2 hosts; they do not play a role in the biological cycle although they may act as agents in perpetuating the infection by feeding dogs with infected meat and viscera.
  • In a food animal, these cysts can be seen at slaughter and are recognised as round swellings in the liver and lungs of infected animals. If a dog is fed, or allowed to scavenge on infected carcasses, the young tapeworms are released from the cysts and grow inside the dog’s intestine. These in turn, produce more eggs and cause further spread of infection.
  • Only 10-20 human cases of this are reported in the UK each year, so it is very rare. Human health protection is an important part and because of that we as a veterinarian recommend a thorough protocol to protect your dog from tapeworms. If you think you may have been exposed to a tapeworm, always contact your GP for advice.

Echinococcus multilocularis tapeworms

  • Echinococcus multilocularis (fox tapeworm) is a small cestode that inhabits the small intestine of foxes, raccoon dogs(coyotes), some other canids and rarely dogs and very seldom cats (definitive hosts). Small rodents are intermediate hosts for E. multilocularis.
  • Infection with the larval stages is transmitted to people through ingestion of food or water contaminated with tapeworm eggs.
  • E. multilocularis causes alveolar echinococcosis which poses a much greater health threat to people than cystic echinocccosis. If left untreated can have potentially fatal consequences. This infection results in the formation of cysts, most commonly in the liver. These occur following the oral ingestion of eggs or proglottids excreted in the faeces of the definitive hosts. They are immediately infective to intermediate hosts including humans.
  • There have been no known domestically acquired cases of Echinococcus multilocularis in the UK. Echinococcus multilocularis is a NOTIFIABLE ANIMAL DISEASE.


Other types of tapeworm can be contracted after scavenging from dead livestock, such as sheep or cattle, being fed raw offal, or hunting rabbits and rodents also pose a risk.

  • Taenia taeniaeformis - cats become infected by ingestion of tissue cyst in rats and mice while they are hunting.
    Prepatent period approx. 5 -10 weeks
  • Taenia hydatigena - dogs become infected when they consume undercooked livestock or venison or feed from dead ruminants (sheep, goats, cattle) or pigs. Dogs are frequently infected through scavenging and predation. Feeding of offal and undercooked meat is also a common practice, especially in working dogs and these dogs are also seasonally more likely to be exposed to carcasses from livestock in the case of farm dogs and from shooting in the case of gun dogs.
    Prepatent period approx. 7 – 10 weeks.
  • Taenia ovis - infects dogs after they consume dead sheep or goat or undercooked lamb meat. Taenia ovis cysts in sheep remain a significant cause of meat condemnation in sheep.
    Prepatent period approx. 6 -8 weeks
  • Taenia multiceps - infects dogs that eat the brains of infected sheep, goat and cattle.
    Prepatent period approx. 6 weeks
  • Taenia crassiceps - which infects dogs when they consume rats and mice
    Prepatent period approx. 4 – 6 weeks
  • Taenia serialis and Taenia pisiformis, which infects dogs when they consume dead rabbits.
    Prepatent period approx. 6 – 8 weeks

Taenia spp. infections do not cause significant symptom in dogs or cats. The mature segments leaving the anus may result in anal pruritus causing an animal to rub its bottom along the ground. Owners may also notice motile segments crawling on the animal’s coat after leaving the anus.

Life cycle

The life cycle of Taenia tapeworms starts in the host’s intestine, the host being a dog or a cat. The adult tapeworm is attached to the intestinal wall and can be unbelievably long (up to 500 cm for Taenia hydatigena) and is made of segments (proglottids). Each segment contains an independent set of organs with new segments being created at the neck while older segments drop off the tail. As a segment matures, its reproductive tract becomes more and more prominent until it consists of a bag of tapeworm eggs. These segments, called proglottids, are passed in the feces and ingested by the intermediate host (mouse, rabbit, sheep etc.).

The young tapeworm hatches in the intermediate host’s intestine and escapes into the blood supply with the next stop being the liver (this new host is a prey animal such as a rodents, rabbit, sheep etc.). The larval tapeworm wanders through the liver, leaving bloody tracks behind. It ultimately falls into the abdominal cavity where it forms a sac. When the intermediate host (rabbit, mouse etc.) dies or is killed by a predator, the sac and its young tapeworm inside may be consumed accidentally.

About 4 to 10 weeks later (pre-patent period), inside the predator (cat, dog etc.), the young tapeworm is now mature and is ready to shed its first segments (proglottids) and the life cycle begins again.

Infection with Taenia spp. can last for several months up to several years, for example Taenia ovis (Taenia species infecting dogs), can be patent for up to 5 years.

Is it Important to Recognize Which Type of Tapeworm the Pet Has?

Dipylidium caninum

The segments of Dipylidium are longer than they are wide and are said to look like grains of rice.

Dipylidium caninum eggs

The segments of a Taenia tapeworm are wider than they are long.

Under the microscope, Taenia eggs and Echinococcus eggs, when they are found, appear identical. They can be distinguished with more advanced testing should this event occur.


Prevention is achieved through the following recommendations:

  • Regular worming treatments.
    We recommend treating your pets for tapeworms once every 3 months. For dogs with a high risk of infection with Echinococcus spp., ESCCAP (European Scientific Counsel Companion Animal Parasites) promotes monthly treatments with an appropriate anthelmintic containing praziquantel or epsiprantel.
  • If possible, dogs and cats should not have access to wild rodents.
  • Cook any meat thoroughly. This will kill any tapeworms that may be present.
  • Dogs and cats should not be given slaughter waste or raw meat but only commercial food or meat that has been heated for 10 minutes (inner temperature: 65°C) or frozen for one week at -17 to -20°C.
  • Dogs imported from endemic areas should be promptly seen by a veterinarian and treated with an appropriate anthelmintic containing praziquantel or epsiprantel.
  • Cats are comparatively unsuitable hosts for E. multilocularis. Even in infected cases, cats only excrete a low number of eggs which have not shown to be infectious under experimental conditions, therefore representing a fractional risk. However, as a precaution, cats with excretion of taeniid eggs should be treated appropriately.
  • Keeping your dogs and cats up to date with flea treatments. This will also reduce the risk of fleas infecting your dog with a tapeworm.
  • Clean up after your dog quickly.
    By picking up your pet’s poop every time, you’re helping to cut the number of tapeworm eggs in the environment and prevent further spread of tapeworms.