Worm Advice

Recognising Parasites and The Symptoms

Believe it or not, but some people may not recognise that their pet has a parasite problem. Many symptoms are external and obvious, but still there is confusion as to what causes them. Many parasites, however, are internal and cannot be seen with your naked eye.

Either way, you’ll need to know how to recognise when a potential parasite infestation is occurring and which parasite it’s likely to be. When you can do this, you are much more likely to know there is a problem and get the necessary treatment.

Internal worms

Most worms that pose a threat to pets are internal, affecting areas such as the small intestines, large intestines, pulmonary arteries, heart and airways in the lungs. As they are inside the body you won’t be able to check for these, but there are noticeable symptoms that can occur that may indicate your dog or cat has some kind of parasitic worm.

Let’s take a look at the main parasitic worms and what symptoms and signs are assigned to each. Some symptoms may be very similar and hard to identify, but you will at least know that something is wrong and seek veterinary treatment. Your vet will be able to do the investigating and take it from there, which usually involves physical examinations, inspecting faeces for any presence of worms or larvae and other tests. Worms can be seen in faeces or in the fur around the animal’s anus and will look like white specks, grains or worms, but some are too small to notice.

Heartworm: Symptoms during or after a trip abroad, problems breathing, lethargy, high blood pressure, coughing that doesn’t go away, decreased levels of activity, tires easily, poor appetite and weight loss.

Hookworm: Anaemia noticeable by pale gums and other mucous membranes, extreme weight loss, lethargy, diarrhoea, bloody or tarry diarrhoea, weakness, paw lesions, constipation, and decreased appetite. However, in some cases, very few signs can show at all.

Lungworm: Feeling fatigued quickly, persistent cough, weight loss, decreased appetite, diarrhoea, vomiting, seizures, mild injuries profusely bleeding, shortness of breath, mucous build-up and coughing up fluids.

Roundworm: Poor condition of coat, diarrhoea, presence of a pot belly, thin appearance, vomiting, anaemia seen by pale mucous membranes, coughing, and signs of poor growth. In some cases, roundworms won’t display external symptoms.

Tapeworm: A tapeworm infestation will not always show symptoms externally. You may notice worm segments in your pet’s faeces or on the fur around the anus, bottom dragging on the floor, irritation, persistent licking or scratching the rear, diarrhoea, vomiting, and in cases of severe infestation, weight loss.

Whipworm: Runny, sometimes bloody diarrhoea with straining, anaemia shown by pale mucous membranes, poor growth, weight loss and low energy levels.


Fox lungworm: Problems breathing, coughing, retching and nasal discharge.

If you notice any of these symptoms you must act quickly. Some cases of worms can end in serious illness or even death, so quick treatment will be needed. Even the worms that cause only minor problems and go away over time will be better off treated to effectively get rid of the parasites completely without causing internal damage.

Fleas and flea larvae


Noticing your pet has fleas will be a little easier than an internal parasite. Pets will scratch excessively or possibly bite at areas of the body. Cats may groom themselves persistently instead of routinely in an attempt to rid themselves of the fleas. Pets may be irritated by flea bite dermatitis and flea allergy dermatitis where the pet has an allergic reaction to the flea’s saliva.

Severe cases of fleas where there are high numbers may cause anaemia, too many fleas are feeding off the animal’s blood over a lengthy period of time. Pale gums or lips and other mucous membranes are the easiest indicator for anaemia you can check.

Fleas can be more dangerous than you think as they are capable of carrying diseases – bacterial and viral diseases can be passed onto the pet. You can learn more about the health risks parasites such as fleas have on your pet in a later chapter.

Checking for fleas: You should check your pet for fleas regardless of whether you suspect them or not. Use a fine comb to check through the fur. Fleas will appear as dark moving specks in the fur or coming off onto the comb teeth. Dark specks that don’t move are actually flea excretion. Tiny white specks are likely to be flea eggs. Check the whole body, particularly the neck area and tail base.



A bad infestation of ticks can lead anaemia, so look for pale gums and lips. Anaemia, however, can indicate other medical problems or infestation of other parasites, so you need to check for the specific problem. You will know it is ticks just by their unique appearance.

Ticks can pass on serious diseases, so symptoms such as poor appetite, high temperature, problems breathing, stiffness, depression, swellings, sensitivity and jaundice may be present. Outside the UK, ticks can transmit other diseases. The health risks chapter will detail these tick-related diseases.

Checking for ticks: The most obvious sign your pet has ticks is by noticing them buried in their skin. You can check for ticks when you check for other. Routinely and regularly check through the fur and do this thoroughly by putting a little bit of pressure so you do not miss any lumps. Tick checking needs to be meticulous, so this means looking at the armpits, ears, between toes and similar easy-to-ignore nooks and crannies.

The size of a tick depends on how long it has been feeding on the blood of your pet. Seeing any pea-shaped bumps embedded in the skin ranging from pinhead to hazelnut in size could be a tick. Their colour can be dark, but a tick that has recently fed may be greyer in colour. You can learn about how to get rid of these ticks if found in a later chapter.

Ear mites

Sometimes ear mites will not show obvious signs of infestation. Symptoms can be persistent head shaking, ear rubbing, ear scratching, skin problems, fur loss, dark and waxy discharge, strong smell from the ear, a swollen ear, dark fragments in the ear canal, trauma and wounds from too much shaking or scratching of the ear – aural haematomas being an example, which involves blood accumulating in the ear causing swelling from rupture blood vessels. The ear flap is basically a pouch and will fill with blood – you will notice the swelling immediately.

As ear mites are so contagious, you may find other pets in your household having similar symptoms.

Checking for ear mites: Though you can see from symptoms alone, you can also check the ear to be sure. You might want to wear some medical gloves. Gently open up the ear for inspection and check for inflammation, redness, debris, discharge, an odour or anything else unusual. Ear mites will look like small dark specks. You can also use a cotton swab to check wax, but only do this if you are sure not to hurt your pet or make the problem worse. Some people look at the wax from the swab under a magnifying glass to check for tiny white dots.


Symptoms of lice are easy to find if you focus on how the lice affects the skin it feeds upon. You should suspect lice more so if your pet is a puppy or kitten, of senior age or in weak health. Your pet will appear to scratch what seems to be very severe itching. This scratching can end up causing trauma to the skin which leads to red, inflamed skin, fur loss and infections.

Your pet’s coat may also experience changes and appear more dull than normal. Lice can also cause anaemia, like many other blood-eating parasites. Once again, pale gums or lips can indicate this.

Checking for lice: You can examine your pet’s fur with a comb. Look out for oval-shaped lice that appear flat lying on the skin or fur. They can often resemble very small white grains, like miniature rice. They are more likely to be seen around the neck, on the head and surrounding the ears.

Sarcoptic and demodex mange mites

Sarcoptic mange mites can cause a lot more than an itch for your pet. They will experience intense irritation to their skin, constant scratching, fur loss, redness, scaled and wrinkled skin, skin sores and infections and disease to the skin. Skin problems are more likely to occur around the ears, face, legs, elbows, groin area and abdomen, with potential to spread in other areas of the body.

Demodex mites will show a milder version of what sarcoptic mange can cause with itchiness still present. Fur loss and small areas of balding, sores and scabs are still likely. Bacterial infections can occur.

Checking for mange mites: As mange mites can transfer to humans, you must be careful and avoid close contact with an infested pet. The mites are normally oval in shape and light in colour, but are microscopic and tricky to diagnose. If you suspect mange mites go to your vet for a confirmed diagnosis and treatment.

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