Parasites are not something we really like to think about, but as responsible owners we need to safeguard our pets, and our families against them. A heavy burden of worms can cause suffering and illness in our pets, so it is very important that we prevent this. Although it is rare, some types of worms also pose a risk to human health if the eggs or larvae are ingested. .
There are two main types of worms affecting dogs and cats
Dipylidium Caninum (the flea tapeworm)
- These are long, flat worms with segmented bodies that attach to the wall of the small intestine and absorb nutrients as they flow past.
- Once tapeworms mature, they shed their segments which pass out in the faeces and look like tiny, mobile, grains of rice.
- The segments dry up in the environment and then break open to release tiny tapeworm eggs.
- The eggs are then eaten by flea larvae in the environment and and they continue part of their lifecycle in this host animal.
- If a dog or cat accidentally swallows a flea when grooming it will become infected with tapeworms again.
- These tapeworms need intermediate hosts such as rabbits, rodents and other animals that may be prey for our dogs and cats.
- The prey species may ingest the tapeworm eggs from the environment and the tapeworm larvae then starts to develop inside its immediate host.
- Once the dog or cat has ingested it’s prey, the tapeworm latches on to the wall of the intestine and continues it’s life cycle in much the same way as the flea tapeworm.
Toxocara Cati & Toxocara Canis
- These worms generally look a lot like small noodles or spaghetti strands and live in the intestine
- Adult roundworms mature, mate and then shed lots of tiny eggs which pass out in the faeces.
- The eggs have a very tough shell and can remain in the environment for a long time.
- Animals ingest the eggs through normal grooming or eating and infected host animal.
- Roundworms can also be passed from mother to puppies or kittens during pregnancy or while nursing.
- When the eggs reach the animals intestines they hatch and the juvenile worm then burrows out of the intestines.
- If the host is not a dog or a cat then the worm encysts (or encloses) itself into other body tissues and waits until the host is eaten by a dog or a cat.
- If the host is a dog or a cat, that has either ingested the worm eggs or has ingested a host animal, the juvenile worms migrate through the body until they reach the lungs; here they are coughed up and then swallowed so that they end up in the intestine again.
- The worms mature in the intestines and eventually produce eggs which are passed out in the dog or cat faeces to begin the life cycle again.
- These Roundworms do not migrate around the body in the same way as the Toxocara species do. The second stage larvae mature in the intestine over a period of 2 to 3 months before they start producing eggs again.
- Lungworms live in the pulmonary arteries and an infestation can be fatal
- They are transmitted to dogs and cats that eat infected slugs, snails and frogs
- For more information on Lungworm please see the links below
Other less common worm types
- These worms mainly affect dogs in the UK and rarely cats.
- In addition to living in the animal’s small intestine, the hookworm larvae can penetrate skin (usually the feet) and cause infection.
- Hookworms are thought to infect up to 68% of the fox population.
- These worms live in the dog’s large intestine. (they don’t affect cats)
- Dog’s become infected by ingesting eggs in the environment that have been passed in faeces of infected dogs.
- These worms are not found in the UK, but they do pose a big risk for animals travelling abroad from the UK.
- They are transmitted by mosquitoes and live in the pulmonary arteries and heart of infected dogs and cats.
Signs that your pet may have worms
- Small white segments (roughly the size of a grain of rice) may be seen around your pet’s bottom area or in the faeces
- Your pet may cough up / vomit Roundworms if he or she has a heavy infestation
- Itchy bottoms may cause them to ‘Scoot’ along the ground
- You may see worms in your pets poo
- Increased appetite
- Vomiting and/or Diarrhoea
- Weight loss
- Loss of coat condition
- Pot belly – usually only seen in puppies or kittens
You may not realise you pet has worms at all because not all pets show these signs. Remember, prevention is easier than cure.
The risk to humans
Toxocariasis is thankfully rare in the UK but can happen when Roundworm larvae are ingested by a human. Usually the larvae will just die off in the human digestive tract, but in some cases the larvae survive and can migrate and encyst in organs or they reach the eye and cause blindness. Children are at a much higher risk of infection as they are often close to pets and play in outdoor areas where parasites may have been deposited.
Keep your pet and the environment worm free
- Use a veterinary recommended wormer. Prescription worming products are usually more effective than over the counter products. You should worm your pet at least 4 times a year, but more frequently if you pet hunts, likes to eat dead animals, or likes to eat poo. Be very careful about using ‘natural/herbal worming products’ as these products work by removing the worms from the animals digestive system but not necessarily killing the worms, meaning any eggs that are passed are still viable and will infect the next host. (It is worth noting that commonly named ‘natural’ worming products such as Oregon Grape, Black Walnut, Wormwood, Garlic and Onions can all be highly toxic to pets!)
- Use a veterinary recommended flea treatment. Prescription flea treatments are usually more effective than over the counter products. Spot on treatments and tablets are usually given monthly and some veterinary recommended flea collars last for up to 8 months . Make sure you use a house-hold spray yearly to kill any flea eggs or larvae in the home environment.
- Scoop the poop; This is important both on walks and in your on garden – it is also against the law to leave your dog’s faeces in public places. Cat litter trays/toileting areas should be scooped out daily and properly cleaned at least once a week.
- Good personal hygiene and making sure children wash their hands, especially after stroking pets and playing outside. Kissing your pet or letting him or her lick your face will put you more at risk, especially if you are immunocompromised.
- Speak to your veterinary nurse. He or she can advise you on the safest and most effective parasite treatments for your pet as well as how often you need to give them.
For more information on the Flea lifecycle
For more information on Lungworm
Novartis Worming information – Worm Patrol
Bayer Animal Health parasite information – Its A Jungle Out There