Worming - Factsheet

Cats and dogs are prone to infestation with worms. These include roundworms, tapeworms and hookworms. Virtually even kitten or pup excretes them soon after birth, and they pass out in their motions. Adults are less likely to have large numbers, but can be infected with different sorts to young animals.

WHY WORM?

The reasons that worming are important are not the most obvious ones. To understand why worms are a problem we need to consider their life cycle and what they do to animals.

Roundworms

These can be picked up as eggs from the environment, swallowed and then they develop through three or four larval stages into adult that live in the gut. Here they absorb nutrients very efficiently, to the extend that young animals may become malnourished and anaemic because of them. Their eggs are shed in motions to the environment. These eggs are very hard and can last for many years. They are also sticky - if picked up they do not get removed by washing hands.

Roundworms are also passed on from the mother to her young before they are born. For some complex biological reason, pregnant dams release all their own larval forms of the worm and they pass across the placenta to the unborn foetus.

Example of roundworms: toxocara

Tapeworms

These are picked up either by eating under-cooked or raw beef or lamb, by eating infected mice and birds, or are passed on by fleas. The most common are those passed by fleas, so if there has been a problem with these, then the chances are that your pet will have tapeworms. They tend to the main problem in adult cats and dogs. They rarely cause a clinical problem in dogs, but cats can become thin, dull and have a lack-lustre coat.

Examples of tapeworms: taenia (from cattle); dypilidium (from fleas)

...SO WHY WORM?

The obvious reason is to prevent ill-health in your pet. However there is a much more important reason: The larvae from the roundworm can infect humans. Children are at greatest risk because they may not have such a good understanding about hygiene, and because they are more likely to come into contact with the eggs when they play outside.

The larvae are extremely small compared to the size of the human body, and most larvae settle in unimportant places where they remain for life, walled off in a fibrous capsule. However, they can settle in delicate areas such as the eye or the brain. Here the fibrous coats can get in the way of normal function, causing blindness or brain problems. It has been shown that 50% of people with epilepsy for which no obvious cause has been assigned have signs of infection with roundworms. Treatment is not possible because the damage has already be done.

Therefore worming of cats and dogs is important to prevent human infection.

It is also a sign of responsible ownership and should be part of your routine health programme

How often should I worm?

The life cycle of the roundworm and tapeworm is about three months. Therefore if a dose of wormer is used at this interval then there should never be a problem. However it has to be the right wormer: Most readily available wormers do not kill the eggs or larvae, so if these are used then for full control a dose needs to be given every month. This becomes both impractical and expensive.

Therefore always use a complete wormer that kills all stages of all worms. These tend to be drugs with prescription licenses, but can be picked up from the practice without the need for us to see the patient provided that they are at least registered with us.

Preventing Infection in pets

1. Pregnant pets should be wormed during pregnancy and immediately afterwards.
2. Try and prevent your pet from scavenging or eating matter from other animals
3. Dispose of all motions immediately
4. Under-cooked and raw meat are problems so avoid feeding these.
5. In SW England certain particularly unpleasant types of worm can be picked up. Therefore if you have visited this area worm your dog upon your return.

Preventing Infection in Humans

1. Wash hands thoroughly with soap before eating
2. Instruct children about hygiene
3. Use gloves to dispose of excrement
4. Use gloves when gardening - remember cats cover their motions so they will not be visible.
5. Worm your pets regularly with a reliable product that kills the egg stages of the worm
6. Humans have on occasions become infected through eating under-cooked meat - beware!

Further Information

We are happy to discuss the issue in more detail, and will do so in the strictest confidence, either at the practice or by telephone. We can also provide leaflets that give more information.

Your doctor should be consulted if you consider that you may have been at risk.

We consider it our duty to encourage responsible pet ownership and our commitment extends to the well being of our clients and the public in general. This information sheet is one of a series produced by The Park Veterinary Practice for educational purposes.