Animal diseases that can affect humans are called zoonoses. There are several dog diseases that may cause disease in your child; here we will look at three "worms" that can spread from dog to human.

Intestinal Worms are a very common parasite of dogs, and can make your dog unwell. Treating your dog regularly with an appropriate worming medication will prevent them from becoming a problem in your dog.

It's a much bigger problem if dog worms have infected your child. Every year thousands of blood tests are performed to check if a person is infected with worms from their dog.

The culprits that may affect your child are hookworms and roundworms.

There are four ways dogs can become infected with hookworms. They may inadvertently eat hookworm larvae, or the larvae penetrate the skin and enter the body that way. Puppies can be infected in the uterus, or by drinking mother's milk containing larvae.

The adult worms attach to the lining of the small intestine and drink blood. An affected dog will have pale gums, black sticky diarrhea and will be quite lethargic because of blood loss.

Adult hookworms don't infect humans, but larvae in the ground may burrow through the skin. They then migrate under the skin, causing red itchy rashes which may become infected. Rarely, it can cause gastrointestinal illness in people.

Canine roundworms are much more dangerous in humans.

This worm again lives in a dog's small intestine, and causes diarrhea, a pot belly and, if there are enough of them, they can block the intestine.

Humans are infected when they inadvertently eat roundworm eggs in the environment. Because young children are usually attracted to dogs, and often put their fingers in their mouths, they are at most risk of getting roundworms.

In most cases, the worms cause no problem to people. However, there is the possibility that roundworm larvae will migrate through the body, particularly through the eye and the brain. The damage they cause is often permanent.

There are three main ways of preventing your children becoming infected with dog worms.Firstly, treat your dog regularly with an effective worming medication to prevent your yard becoming infected with eggs or larvae. Secondly, teach your child proper hygiene around dogs - wash their hands after patting the family pet, and encourage them to keep their hands out of their mouths. Lastly, clean up feces around the yard, as they'll be a source of infection.

Ringworm isn't in fact a worm at all, it is a fungal infection. It gets it's name because it often causes a hairless round patch on the skin of both dogs and people, which can be red and itchy. The infected patch heals from the middle outwards, so it looks like a red ring on the skin.

In some cases, dogs can have ringworm without showing any skin changes. Also, the fungal spores live a long time in the environment. Spread is through contacting the spores, either through patting an infected dog, or handling bedding or grooming tools such as brushes.

Depending on the severity, you and your dog will be treated with an ointment, or with tablets. Because an infected dog is constantly shedding spores, you have to be persistent to completely eliminate the infection. Fortunately, ringworm is usually not a severe condition, and is easily treated.

Teaching your child good hygiene will help prevent infection with these worms, and keep your child healthy.