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Roundworms are zoonotic parasites, which means they can be passed from animals to humans - especially children. They can also be exceptionally good survivors, with viable eggs able to live outside the animal for several years. Roundworm symptoms include vomiting, diarrhoea, pot-belly and colic. Puppies can develop roundworm at the foetal stage, prior to being born.


The most dangerous of all intestinal worms, hookworms survive by burrowing into a pet's intestinal wall and sucking blood. Female hookworms can lay up to 30,000 eggs daily. These hatch in the faeces. Infection is caused by swallowing or skin penetration. Your cat or dog could experience enteritis, diarrhoea, dehydration and ultimately death from anaemia. Like roundworms, they are zoonotic parasites and can affect humans.


Common flea tapeworm larvae develop in fleas, and when a pet eats an infected flea while grooming itself, the tapeworm develops in the animal's gut. Other tapeworm larvae develop in rodents that can be eaten by pets, especially cats. While not a major health risk, tapeworms cause itching and can be responsible for dogs rubbing their backsides on the ground, and irritation displayed by cats.

Hydatid tapeworms are found in areas where sheep, or wild pigs are in contact with dogs. After eating hydatid eggs from pastures contaminated by infected dogs, intermediate hosts can develop hydatid cysts. Dogs become infected with the hydatid tapeworms after eating hydatid cysts from infected intermediate hosts (e.g. eating offal from sheep). Hydatid tapeworms pose a serious health risk to humans. The same cysts can occur in adults or children who accidentally swallow eggs from a dog's coat.


Whipworms live in the lower bowel of dogs and can survive for up to a year, laying more than 2000 eggs each day. These eggs are passed in the droppings and can survive in soil and pet surroundings for years. Symptoms include pain, diarrhoea and weight loss.

A regular worming program is essential

While worming is effective in killing worms that are present in the intestine at the time of treatment, worming is not a vaccine against future attacks. This is why regular treatment, especially in your pet's early months, is essential to the pet's health. Dogs and cats can be re-infected from other pets and from the environment.