Many people think that if they have not seen any sign of worms in their pet’s faeces then they do not need to bother with routine worming.

This is a commonly held belief but not true.  Dogs and cats do not often pass worms in the faeces unless they have a heavy worm burden.  So what are these worms and why do we need to worry about them?


Roundworms are spaghetti-like in appearance.  Almost all puppies and kittens are infected with them while in the uterus or soon after birth via the mother’s milk.  A mild infestation in a young animal can cause vomiting, diarrhoea, a pot belly and poor growth while a severe infestation can prove fatal.  Therefore it is vitally important to worm regularly from two weeks old.

Roundworm can also be passed between adult pets via eggs and larvae in faeces.  A heavy infestation in an adult animal can cause ill health but more often than not, adult animals carrying worms show no signs.

So why is it so important to worm adult pets regularly then?  The main reason is public health.  Human infection with a common roundworm called Toxacara can occur.  It is relatively rare but the consequences can be serious including blindness.  It is likely that many more people have been exposed to the parasite without realising it, experiencing milder symptoms.  Children are at higher risk than adults.


These also live in the small intestine and the tapeworm segments look like grains of rice.  Their spread is closely linked to the flea lifecycle so good flea control is an important part of prevention.  Hunting cats are also infected via infected mice.


Lungworm is an infection carried by slugs and snails.  Slugs and snails carry the lungworm larvae and if they or their slime trail are eaten by a dog, the larvae can travel to the heart and blood vessels of the lungs.  Signs can include coughing, respiratory problems, blood clotting disorders and seizures and the disease can prove fatal.

Lungworm used to be confined to the south of the United Kingdom but has recently been diagnosed all over the country including East Anglia.

So how do I prevent worms?

In general we would recommend worming all dogs and cats at least every three months.  There are situations when worming more regularly is advised.  For example if there are young children in the house or if you have a cat who hunts regularly then monthly worming should be considered.  Lungworm prevention also requires monthly worming and many of the over the counter products available in pet stores and supermarkets have no action against lungworm.

So the best advice is to mark on your calendar when your pet’s worming is due so it does not get forgotten in the busy lives we all lead and consult your veterinary practice for advice on a worming protocol and product specifically tailored to the lifestyle of your pet